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<section id="scylladb-faq">
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<h1>ScyllaDB FAQ<a class="headerlink" href="#scylladb-faq" title="Link to this heading">¶</a></h1>
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<section id="performance">
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<h2>Performance<a class="headerlink" href="#performance" title="Link to this heading">¶</a></h2>
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<section id="scylladb-is-using-all-of-my-memory-why-is-that-what-if-the-server-runs-out-of-memory">
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<h3>ScyllaDB is using all of my memory! Why is that? What if the server runs out of memory?<a class="headerlink" href="#scylladb-is-using-all-of-my-memory-why-is-that-what-if-the-server-runs-out-of-memory" title="Link to this heading">¶</a></h3>
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<p>ScyllaDB uses available memory to cache your data. ScyllaDB knows how to dynamically manage memory for optimal performance; for example, if many clients connect to ScyllaDB, it will evict some data from the cache to make room for these connections; when the connection count drops again, this memory is returned to the cache.</p>
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<section id="can-i-limit-scylladb-to-use-less-cpu-and-memory">
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<h3>Can I limit ScyllaDB to use less CPU and memory?<a class="headerlink" href="#can-i-limit-scylladb-to-use-less-cpu-and-memory" title="Link to this heading">¶</a></h3>
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<p>The <code class="code docutils literal notranslate"><span class="pre">--smp</span></code> option (for instance, <code class="code docutils literal notranslate"><span class="pre">--smp</span> <span class="pre">2</span></code>) will restrict ScyllaDB to a smaller number of CPUs. It will still use 100 % of those CPUs, but at least won’t take your system out completely. An analogous option exists for memory: <code class="code docutils literal notranslate"><span class="pre">-m</span></code>.</p>
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</section>
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<section id="what-are-some-of-the-techniques-scylladb-uses-to-achieve-its-performance">
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<h3>What are some of the techniques ScyllaDB uses to achieve its performance?<a class="headerlink" href="#what-are-some-of-the-techniques-scylladb-uses-to-achieve-its-performance" title="Link to this heading">¶</a></h3>
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<p>ScyllaDB tries to utilize all available resources (processor cores, memory, storage, and networking) by always operating in parallel and never blocking. If ScyllaDB needs to read a disk block, it initiates the read and immediately moves on to another task. Later, when the read completes ScyllaDB resumes the original task from where it left off. By never blocking, a high degree of concurrency is achieved, allowing all resources to be utilized to their limit.
|
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Read more on ScyllaDB Architecture:</p>
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<ul class="simple">
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<li><p><a class="reference external" href="http://www.scylladb.com/product/technology/">ScyllaDB Technology</a></p></li>
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<li><p><a class="reference external" href="http://www.scylladb.com/product/technology/memory-management/">ScyllaDB Memory Management</a></p></li>
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</ul>
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</section>
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<section id="i-thought-that-scylladb-s-underlying-seastar-framework-uses-one-thread-per-core-but-i-see-more-than-two-threads-per-core-why">
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||
<h3>I thought that ScyllaDB’s underlying <a class="reference external" href="https://github.com/scylladb/seastar">Seastar framework</a> uses one thread per core, but I see more than two threads per core. Why?<a class="headerlink" href="#i-thought-that-scylladb-s-underlying-seastar-framework-uses-one-thread-per-core-but-i-see-more-than-two-threads-per-core-why" title="Link to this heading">¶</a></h3>
|
||
<p>Seastar creates an extra thread per core for blocking syscalls (like <code class="code docutils literal notranslate"><span class="pre">open()</span></code>/ <code class="code docutils literal notranslate"><span class="pre">fsync()</span></code> / <code class="code docutils literal notranslate"><span class="pre">close()</span></code> ); this allows the Seastar reactor to continue executing while a blocking operation takes place. Those threads are usually idle, so they don’t contribute to significant context switching activity.</p>
|
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</section>
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<section id="im-seeing-x-compaction-running-in-parallel-on-a-single-scylladb-node-is-it-normal">
|
||
<h3>I’m seeing X compaction running in parallel on a single ScyllaDB node. Is it normal?<a class="headerlink" href="#im-seeing-x-compaction-running-in-parallel-on-a-single-scylladb-node-is-it-normal" title="Link to this heading">¶</a></h3>
|
||
<p>Yes, for more than one reason:</p>
|
||
<ul class="simple">
|
||
<li><p>each shard (core) will run its compactions independently, often at the same time,</p></li>
|
||
<li><p>each table will run its compactions independently, often at the same time</p></li>
|
||
<li><p>depending on the compaction strategy, more than one compaction can run in parallel. For example in Sized Tier Compaction Strategy (STCS), large sstable compaction can take time, allowing smaller sstable to be compacted at the same time</p></li>
|
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</ul>
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</section>
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||
<section id="setting-io-conf-configuration-for-hdd-storage">
|
||
<span id="faq-io"></span><h3>Setting io.conf configuration for HDD storage<a class="headerlink" href="#setting-io-conf-configuration-for-hdd-storage" title="Link to this heading">¶</a></h3>
|
||
<p>As part of the ScyllaDB setup process, <strong>iotune</strong> runs a short benchmark of your storage. When completed, it generates the <cite>/etc/scylla.d/io.conf</cite> configuration file. Note that iotune has known issues benchmarking HDD storage.</p>
|
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<div class="admonition note">
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<p class="admonition-title">Note</p>
|
||
<p>This section is not relevant in 2.3</p>
|
||
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||
<p>Therefore, when using ScyllaDB with HDD storage, it is recommended to use RAID0 on all of your available disks, and manually update the <cite>io.conf</cite> configuration file <cite>max-io-request</cite> parameter. This parameter sets the number of concurrent requests sent to the storage. The value for this parameter should be 3X (3 times) the number of your disks. For example, if you have 3 disks, you would set <cite>max-io-request=9</cite>.</p>
|
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</section>
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<section id="how-many-connections-is-it-recommended-to-open-from-each-scylladb-client-application">
|
||
<h3>How many connections is it recommended to open from each ScyllaDB client application?<a class="headerlink" href="#how-many-connections-is-it-recommended-to-open-from-each-scylladb-client-application" title="Link to this heading">¶</a></h3>
|
||
<p>As a rule of thumb, for ScyllaDB’s best performance, each client needs at least 1-3 connection per ScyllaDB core.
|
||
For example, a cluster with three nodes, each node with 16 cores, each client application should open 32 (2x16) connections to each ScyllaDB node.</p>
|
||
</section>
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||
<section id="do-i-need-to-configure-swap-on-a-scylladb-node">
|
||
<h3>Do I need to configure <code class="docutils literal notranslate"><span class="pre">swap</span></code> on a ScyllaDB node?<a class="headerlink" href="#do-i-need-to-configure-swap-on-a-scylladb-node" title="Link to this heading">¶</a></h3>
|
||
<p>Yes, configuring <code class="docutils literal notranslate"><span class="pre">swap</span></code> on a ScyllaDB node is recommended.
|
||
<code class="docutils literal notranslate"><span class="pre">swap</span></code> size should be set to either <code class="docutils literal notranslate"><span class="pre">total_mem</span></code>/3 or 16GB - lower of the two.</p>
|
||
<p><code class="docutils literal notranslate"><span class="pre">total_mem</span></code> is the total size of the nodes memory.</p>
|
||
<p>For example:</p>
|
||
<ul class="simple">
|
||
<li><p>If the node <code class="docutils literal notranslate"><span class="pre">total_mem</span></code> is 18GB <code class="docutils literal notranslate"><span class="pre">swap</span></code> size should be set to 6GB.</p></li>
|
||
<li><p>If the node <code class="docutils literal notranslate"><span class="pre">total_mem</span></code> is 240GB <code class="docutils literal notranslate"><span class="pre">swap</span></code> size should be set to 16GB.</p></li>
|
||
</ul>
|
||
<p>Swap can be set up in several ways. One way to set up swap is detailed in the KB Article <a class="reference internal" href="kb/set-up-swap.html"><span class="doc">How to Set up a Swap Space</span></a>.</p>
|
||
</section>
|
||
<section id="my-query-does-not-return-any-or-some-of-the-data-what-happened">
|
||
<h3>My query does not return any or some of the data? What happened?<a class="headerlink" href="#my-query-does-not-return-any-or-some-of-the-data-what-happened" title="Link to this heading">¶</a></h3>
|
||
<p>If you are using a time range in the query, refer to the solution in the troubleshooting document, <a class="reference internal" href="troubleshooting/time-zone.html"><span class="doc">Time Range Queries Do Not Return Some or All of the Data</span></a>.</p>
|
||
</section>
|
||
<section id="desc-schema-shows-that-i-am-using-many-materialized-views-mvs-when-i-know-i-only-added-secondary-indexes-si-why-are-there-mvs-in-my-schema">
|
||
<h3>DESC SCHEMA shows that I am using many materialized views (MVs) when I know I only added Secondary Indexes (SI). Why are there MVs in my schema?<a class="headerlink" href="#desc-schema-shows-that-i-am-using-many-materialized-views-mvs-when-i-know-i-only-added-secondary-indexes-si-why-are-there-mvs-in-my-schema" title="Link to this heading">¶</a></h3>
|
||
<p>As SI is built on top of MV, you can expect to see MV in your schema. There is nothing wrong with your system. More information on <a class="reference internal" href="features/secondary-indexes.html"><span class="doc">Global Secondary Indexes</span></a>.</p>
|
||
</section>
|
||
<section id="using-the-java-driver-simplestatements-are-slow-why-does-this-happen">
|
||
<h3>Using the Java driver SimpleStatements are slow. Why does this happen?<a class="headerlink" href="#using-the-java-driver-simplestatements-are-slow-why-does-this-happen" title="Link to this heading">¶</a></h3>
|
||
<p>The Java driver’s <a class="reference external" href="https://java-driver.docs.scylladb.com/stable/manual/statements/simple/">SimpleStatement</a> is token unaware by default. This means that requests sent out will reach the Controller node before it is known which shard it’s supposed to access. We suggest using <a class="reference external" href="https://java-driver.docs.scylladb.com/stable/manual/statements/prepared/">PreparedStatements</a> instead.</p>
|
||
</section>
|
||
</section>
|
||
<section id="disk-space">
|
||
<h2>Disk Space<a class="headerlink" href="#disk-space" title="Link to this heading">¶</a></h2>
|
||
<section id="dropping-a-table-does-not-reduce-storage-used-by-scylladb-how-can-i-clean-the-disk-from-dropped-tables">
|
||
<span id="reclaim-space"></span><h3>Dropping a table does not reduce storage used by ScyllaDB, how can I clean the disk from dropped tables?<a class="headerlink" href="#dropping-a-table-does-not-reduce-storage-used-by-scylladb-how-can-i-clean-the-disk-from-dropped-tables" title="Link to this heading">¶</a></h3>
|
||
<p>scylla.yaml includes an <code class="docutils literal notranslate"><span class="pre">auto_snapshot</span></code> parameter; when true (it is by default), ScyllaDB creates a snapshot for a table just before dropping it, as a safety measure.
|
||
You can find the snapshot in the <code class="docutils literal notranslate"><span class="pre">snapshots</span></code> directory, under the table SSTable. For example, for dropped table <code class="docutils literal notranslate"><span class="pre">users</span></code> in keyspace <code class="docutils literal notranslate"><span class="pre">mykeyspace</span></code>:</p>
|
||
<p><code class="code docutils literal notranslate"><span class="pre">/var/lib/scylla/data/mykeyspace/users-bdba4e60f6d511e7a2ab000000000000/snapshots/1515678531438-users</span></code></p>
|
||
<p>As the snapshot take the same space as the dropped table, disk usage will remain the same.
|
||
You can clean snapshots by using <a class="reference internal" href="operating-scylla/nodetool-commands/clearsnapshot.html"><span class="doc">nodetool clearsnapshot</span></a>. Read more on <a class="reference internal" href="operating-scylla/procedures/backup-restore/delete-snapshot.html"><span class="doc">snapshot and clearsnapshot</span></a></p>
|
||
</section>
|
||
</section>
|
||
<section id="features">
|
||
<h2>Features<a class="headerlink" href="#features" title="Link to this heading">¶</a></h2>
|
||
<section id="i-want-to-try-out-new-features-how-do-i-enable-experimental-mode">
|
||
<h3>I want to try out new features. How do I enable experimental mode?<a class="headerlink" href="#i-want-to-try-out-new-features-how-do-i-enable-experimental-mode" title="Link to this heading">¶</a></h3>
|
||
<p>You need to add the line <code class="code docutils literal notranslate"><span class="pre">experimental:</span> <span class="pre">true</span></code> to your <code class="code docutils literal notranslate"><span class="pre">scylla.yaml</span></code> file.</p>
|
||
<ol class="arabic">
|
||
<li><p>Launch the file in a text editor: <code class="code docutils literal notranslate"><span class="pre">$</span> <span class="pre">vi</span> <span class="pre">/etc/scylla/scylla.yaml</span></code>. (Alternately, on docker, it’s <code class="code docutils literal notranslate"><span class="pre">$</span> <span class="pre">docker</span> <span class="pre">exec</span> <span class="pre">-it</span> <span class="pre">your_node</span> <span class="pre">vi</span> <span class="pre">/etc/scylla/scylla.yaml</span></code>);</p></li>
|
||
<li><p>Add the line <code class="code docutils literal notranslate"><span class="pre">experimental:</span> <span class="pre">true</span></code>;</p></li>
|
||
<li><p>Save the file and exit.</p></li>
|
||
<li><p>Stop and restart the node.</p>
|
||
<p>On RedHat Enterprise Linux, CentOS or Ubuntu:</p>
|
||
<p><code class="code docutils literal notranslate"><span class="pre">$</span> <span class="pre">sudo</span> <span class="pre">systemctl</span> <span class="pre">restart</span> <span class="pre">scylla-server</span></code></p>
|
||
<p>On Docker:</p>
|
||
<p><code class="code docutils literal notranslate"><span class="pre">$</span> <span class="pre">docker</span> <span class="pre">stop</span> <span class="pre"><your_node></span> <span class="pre">&&</span> <span class="pre">docker</span> <span class="pre">start</span> <span class="pre"><your_node></span></code></p>
|
||
<p>Alternately, starting from ScyllaDB 2.0, you can start ScyllaDB for Docker with the <code class="code docutils literal notranslate"><span class="pre">experimental</span></code> flag as follows:</p>
|
||
<p><code class="code docutils literal notranslate"><span class="pre">$</span> <span class="pre">docker</span> <span class="pre">run</span> <span class="pre">--name</span> <span class="pre"><your_node></span> <span class="pre">-d</span> <span class="pre">scylladb/scylla</span> <span class="pre">--experimental</span> <span class="pre">1</span></code></p>
|
||
</li>
|
||
</ol>
|
||
<p>You should now be able to use the experimental features available in your version of ScyllaDB.</p>
|
||
</section>
|
||
<section id="how-do-i-check-the-current-version-of-scylladb-that-i-am-running">
|
||
<h3>How do I check the current version of ScyllaDB that I am running?<a class="headerlink" href="#how-do-i-check-the-current-version-of-scylladb-that-i-am-running" title="Link to this heading">¶</a></h3>
|
||
<ul class="simple">
|
||
<li><p>On a regular system or VM (running Ubuntu, CentOS, or RedHat Enterprise): <code class="code docutils literal notranslate"><span class="pre">$</span> <span class="pre">scylla</span> <span class="pre">--version</span></code></p></li>
|
||
</ul>
|
||
<p>Check the <a class="reference internal" href="getting-started/os-support.html"><span class="doc">Operating System Support Guide</span></a> for a list of supported operating systems and versions.</p>
|
||
<ul class="simple">
|
||
<li><p>On a docker node: <code class="code docutils literal notranslate"><span class="pre">$</span> <span class="pre">docker</span> <span class="pre">exec</span> <span class="pre">-it</span> <span class="pre">Node_Z</span> <span class="pre">scylla</span> <span class="pre">--version</span></code></p></li>
|
||
</ul>
|
||
</section>
|
||
<section id="i-am-upgrading-my-nodes-to-a-version-that-uses-a-newer-sstable-format-when-will-the-nodes-start-using-the-new-sstable-format">
|
||
<h3>I am upgrading my nodes to a version that uses a newer SSTable format, when will the nodes start using the new SSTable format?<a class="headerlink" href="#i-am-upgrading-my-nodes-to-a-version-that-uses-a-newer-sstable-format-when-will-the-nodes-start-using-the-new-sstable-format" title="Link to this heading">¶</a></h3>
|
||
<p>The <a class="reference internal" href="architecture/sstable/sstable3/index.html"><span class="doc">new “mc” SSTable format</span></a> is supported in ScyllaDB 3.0 and later.
|
||
ScyllaDB only starts using the newer format when every node in the cluster is capable to generate it.
|
||
Therefore, only when all nodes in the cluster are upgraded the new format is used.</p>
|
||
</section>
|
||
</section>
|
||
<section id="docker">
|
||
<h2>Docker<a class="headerlink" href="#docker" title="Link to this heading">¶</a></h2>
|
||
<section id="what-if-i-get-an-error-when-connecting-an-application-to-a-scylladb-cluster-in-docker">
|
||
<h3>What if I get an error when connecting an application to a ScyllaDB cluster in Docker?<a class="headerlink" href="#what-if-i-get-an-error-when-connecting-an-application-to-a-scylladb-cluster-in-docker" title="Link to this heading">¶</a></h3>
|
||
<p>Connectivity problems may occur if you are trying to connect to the ScyllaDB nodes with their Docker internal IP addresses.</p>
|
||
<p>If you need to reach your nodes from outside the internal Docker network, you must expose the appropriate ports to the Docker host.
|
||
See <a class="reference external" href="https://stackoverflow.com/questions/72165195/error-connecting-java-spring-application-to-scylladb-cluster-in-docker">Error connecting Java Spring application to ScyllaDB Cluster in Docker</a> for more information and an example.</p>
|
||
</section>
|
||
</section>
|
||
<section id="installation">
|
||
<h2>Installation<a class="headerlink" href="#installation" title="Link to this heading">¶</a></h2>
|
||
<section id="can-i-install-scylladb-on-an-apache-cassandra-server">
|
||
<h3>Can I install ScyllaDB on an Apache Cassandra server?<a class="headerlink" href="#can-i-install-scylladb-on-an-apache-cassandra-server" title="Link to this heading">¶</a></h3>
|
||
<p>ScyllaDB comes with its own version of the Apache Cassandra client tools, in the package <code class="code docutils literal notranslate"><span class="pre">scylla-tools</span></code>. Trying to install it on a server with Cassandra already installed may result in something like:</p>
|
||
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="go">Unpacking scylla-tools (1.0.1-20160411.b9fe89b-ubuntu1) ...</span>
|
||
<span class="go">dpkg: error processing archive /var/cache/apt/archives/scylla-tools_1.0.1-20160411.b9fe89b-ubuntu1_all.deb (--unpack):</span>
|
||
<span class="go">trying to overwrite '/usr/bin/nodetool', which is also in package cassandra 2.1.4</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>We recommend uninstalling Apache Cassandra before installing <code class="code docutils literal notranslate"><span class="pre">scylla-tools</span></code>.</p>
|
||
</section>
|
||
<section id="can-i-install-or-upgrade-to-a-patch-release-other-than-latest-on-debian-or-ubuntu">
|
||
<span id="faq-pinning"></span><h3>Can I install or upgrade to a patch release other than latest on Debian or Ubuntu?<a class="headerlink" href="#can-i-install-or-upgrade-to-a-patch-release-other-than-latest-on-debian-or-ubuntu" title="Link to this heading">¶</a></h3>
|
||
<p>The APT package manager used for Ubuntu, Debian, and image installations of ScyllaDB installs the latest patch
|
||
release (x.y.z) of a given major release (x.y). To remain on a ScyllaDB patch release that is not the latest, you can
|
||
use pinning as a workaround.</p>
|
||
<p>The following example shows pinning ScyllaDB Enterprise version 2021.1.0-0.20210511.9e8e7d58b-1:</p>
|
||
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="gp">$ </span>cat<span class="w"> </span><<EOF<span class="w"> </span><span class="p">|</span><span class="w"> </span>sudo<span class="w"> </span>tee<span class="w"> </span>/etc/apt/preferences.d/99scylla-enterprise
|
||
<span class="go">Package: scylla-enterprise*</span>
|
||
<span class="go">Pin: version 2021.1.0-0.20210511.9e8e7d58b-1</span>
|
||
<span class="go">Pin-Priority: 1001</span>
|
||
<span class="go">EOF</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>Pinning may be particularly useful when you want to downgrade ScyllaDB or upgrade to a version that is not the latest
|
||
available version. See <a class="reference external" href="https://help.ubuntu.com/community/PinningHowto">this article</a> for details about pinning on Debian-based systems.</p>
|
||
<p>Alternatively, you can explicitly install <strong>all</strong> the ScyllaDB packages for the desired non-latest version. For example:</p>
|
||
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="go">sudo apt-get install scylla-enterprise{,-server,-tools,-tools-core,-kernel-conf,-node-exporter,-conf,-python3}=2021.1.0-0.20210511.9e8e7d58b-1</span>
|
||
<span class="go">sudo apt-get install scylla-enterprise-machine-image=2021.1.0-0.20210511.9e8e7d58b-1 # only execute on AMI instance</span>
|
||
</pre></div>
|
||
</div>
|
||
</section>
|
||
<section id="which-snitch-or-replication-strategy-should-i-use">
|
||
<span id="faq-snitch-strategy"></span><h3>Which snitch or replication strategy should I use?<a class="headerlink" href="#which-snitch-or-replication-strategy-should-i-use" title="Link to this heading">¶</a></h3>
|
||
<p>If you are creating a production cluster or if your cluster is going to have more than one data center you need to use a <strong>DC-aware</strong> snitch, e.g. <code class="code docutils literal notranslate"><span class="pre">GossipingPropertyFileSnitch</span></code> or <code class="code docutils literal notranslate"><span class="pre">Ec2MultiRegionSnitch</span></code>. You will also need to use a <strong>DC-aware</strong> replication strategy, e.g. <code class="code docutils literal notranslate"><span class="pre">NetworkTopologyStrategy</span></code>.</p>
|
||
<p>Our general recommendation is to always use a <code class="code docutils literal notranslate"><span class="pre">NetworkTopologyStrategy</span></code> and use <code class="code docutils literal notranslate"><span class="pre">Ec2XXX</span></code> snitches on AWS based clusters and <code class="code docutils literal notranslate"><span class="pre">GossipingPropertyFileSnitch</span></code> in all other cases.</p>
|
||
<p>A description of all snitch options we support may be found in <a class="reference internal" href="operating-scylla/system-configuration/snitch.html"><span class="doc">Snitches</span></a>.</p>
|
||
<p>Note: trying to mix a <code class="code docutils literal notranslate"><span class="pre">SimpleSnitch</span></code> with a <code class="code docutils literal notranslate"><span class="pre">DC-aware</span> <span class="pre">strategy</span></code> or a <code class="code docutils literal notranslate"><span class="pre">DC-aware</span> <span class="pre">snitch</span></code> with a <code class="code docutils literal notranslate"><span class="pre">SimpleStrategy</span></code> may cause your cluster not to work as intended therefore we <strong>strongly discourage</strong> these types of configurations in general.</p>
|
||
<p>Not using a proper snitch-strategy combination may cause different types of errors.</p>
|
||
<p>For instance:</p>
|
||
<div class="highlight-console notranslate"><div class="highlight"><pre><span></span><span class="go">Unavailable: code=1000 [Unavailable exception] message="Cannot achieve consistency level for cl LOCAL_ONE. Requires 1, alive 0" info={'required_replicas': 1, 'alive_replicas': 0, 'consistency': 'LOCAL_ONE'}</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>If you see this error you should always check that you are not using a <code class="code docutils literal notranslate"><span class="pre">SimpleSnitch</span></code> in your cluster configuration in conjunction with some <code class="code docutils literal notranslate"><span class="pre">DC-aware</span> <span class="pre">replication</span> <span class="pre">strategy</span></code> for a keyspace of a table you are failing to query.</p>
|
||
<p>When working with <code class="docutils literal notranslate"><span class="pre">GossipingPropertyFileSnitch</span></code> or <code class="docutils literal notranslate"><span class="pre">Ec2MultiRegionSnitch</span></code> you should edit the <code class="docutils literal notranslate"><span class="pre">cassandra-rackdc.properties</span></code></p>
|
||
<p>For node using <code class="docutils literal notranslate"><span class="pre">GossipingPropertyFileSnitch</span></code>, the file should look like the following:</p>
|
||
<div class="highlight-cql notranslate"><div class="highlight"><pre><span></span><span class="n">dc</span><span class="o">=</span><span class="n">asia_datacenter</span>
|
||
<span class="n">rack</span><span class="o">=</span><span class="n">rack1</span>
|
||
<span class="n">prefer_local</span><span class="o">=</span> <span class="n">true</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>When the node is the Asia data center, on rack1 and to minimize BW usage
|
||
for inter-datacenter, use the prefer_local</p>
|
||
<p>For <code class="docutils literal notranslate"><span class="pre">Ec2MultiRegion</span></code> the file should include the following information</p>
|
||
<div class="highlight-cql notranslate"><div class="highlight"><pre><span></span><span class="n">dc_suffix</span><span class="o">=</span><span class="n">my_dc</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>This will create a suffix for the node location for example:</p>
|
||
<div class="highlight-cql notranslate"><div class="highlight"><pre><span></span><span class="n">us</span><span class="o">-</span><span class="n">east1_my_dc</span>
|
||
</pre></div>
|
||
</div>
|
||
<p>The problem may also arise if you are using some <code class="code docutils literal notranslate"><span class="pre">DC-aware</span> <span class="pre">snitch</span></code>, e.g. <code class="code docutils literal notranslate"><span class="pre">Ec2MultiRegionSnitch</span></code>, and a <code class="code docutils literal notranslate"><span class="pre">SimpleStrategy</span></code> in a multi-DC cluster.</p>
|
||
<p>Please make sure that both the snitch and the replication strategy of the keyspace are <code class="code docutils literal notranslate"><span class="pre">DC-aware</span></code>.</p>
|
||
<p>After that, if you are using a <code class="code docutils literal notranslate"><span class="pre">DC-aware</span></code> configuration, make sure that the replication strategy uses the proper data centers’ names. Verify the data centers names in your cluster using a <code class="code docutils literal notranslate"><span class="pre">nodetool</span> <span class="pre">status</span></code> command.</p>
|
||
</section>
|
||
<section id="can-i-change-the-replication-factor-a-keyspace-on-a-live-cluster">
|
||
<h3>Can I change the replication factor (a keyspace) on a live cluster?<a class="headerlink" href="#can-i-change-the-replication-factor-a-keyspace-on-a-live-cluster" title="Link to this heading">¶</a></h3>
|
||
<p>Yes, but it will require running a full repair (or cleanup) to change the replica count of existing data:</p>
|
||
<ul class="simple">
|
||
<li><p><a class="reference internal" href="cql/ddl.html#alter-keyspace-statement"><span class="std std-ref">Alter</span></a> the replication factor for desired keyspace (using cqlsh for instance).</p></li>
|
||
<li><p>If you’re reducing the replication factor, run <code class="docutils literal notranslate"><span class="pre">nodetool</span> <span class="pre">cleanup</span> <span class="pre"><updated</span> <span class="pre">Keyspace></span></code> on the keyspace you modified to remove surplus replicated data.
|
||
Cleanup runs on a per-node basis.</p></li>
|
||
<li><p>If you’re increasing the replication factor, refer to <a class="reference internal" href="kb/rf-increase.html"><span class="doc">How to Safely Increase the RF</span></a></p></li>
|
||
<li><p>Note that you need to provide the keyspace namr. If you do not, the cleanup or repair operation runs on all keyspaces for the specific node.</p></li>
|
||
</ul>
|
||
</section>
|
||
<section id="why-can-t-i-set-listen-address-to-listen-to-0-0-0-0-all-my-addresses">
|
||
<h3>Why can’t I set <code class="docutils literal notranslate"><span class="pre">listen_address</span></code> to listen to 0.0.0.0 (all my addresses)?<a class="headerlink" href="#why-can-t-i-set-listen-address-to-listen-to-0-0-0-0-all-my-addresses" title="Link to this heading">¶</a></h3>
|
||
<p>ScyllaDB is a gossip-based distributed system and <code class="docutils literal notranslate"><span class="pre">listen_address</span></code> is the address a node tells other nodes to reach
|
||
it at. Telling other nodes “contact me on any of my addresses” is a bad idea; if different nodes in the cluster pick
|
||
different addresses for you, Bad Things happen.</p>
|
||
<p>If you don’t want to manually specify an IP to <code class="docutils literal notranslate"><span class="pre">listen_address</span></code> for each node in your cluster (understandable!), leave
|
||
it blank and ScyllaDB will use <code class="docutils literal notranslate"><span class="pre">InetAddress.getLocalHost()</span></code> to pick an address. Then it’s up to you or your ops team
|
||
to make things resolve correctly (<code class="docutils literal notranslate"><span class="pre">/etc/hosts/</span></code>, dns, etc).</p>
|
||
</section>
|
||
<section id="what-is-the-best-scenario-to-add-a-node-to-a-multi-availability-zone-az">
|
||
<span id="faq-best-scenario-node-multi-availability-zone"></span><h3>What is the best scenario to add a node to a multi availability zone (AZ)?<a class="headerlink" href="#what-is-the-best-scenario-to-add-a-node-to-a-multi-availability-zone-az" title="Link to this heading">¶</a></h3>
|
||
<p>If using three node cluster, with RF=3, each node located on a different availability zone (AZ).</p>
|
||
<p>For example:</p>
|
||
<div class="highlight-shell notranslate"><div class="highlight"><pre><span></span>Datacenter:<span class="w"> </span>DC1
|
||
<span class="nv">Status</span><span class="o">=</span>Up/Down
|
||
<span class="nv">State</span><span class="o">=</span>Normal/Leaving/Joining/Moving
|
||
--<span class="w"> </span>Address<span class="w"> </span>Load<span class="w"> </span>Tokens<span class="w"> </span>Owns<span class="w"> </span><span class="o">(</span>effective<span class="o">)</span><span class="w"> </span>Host<span class="w"> </span>ID<span class="w"> </span>Rack
|
||
UN<span class="w"> </span><span class="m">192</span>.168.1.201<span class="w"> </span><span class="m">118</span>.82<span class="w"> </span>KB<span class="w"> </span><span class="m">256</span><span class="w"> </span><span class="m">33</span>.6%<span class="w"> </span>8d5ed9f4-7764-4dbd-bad8-43fddce94b7c<span class="w"> </span>A1
|
||
UN<span class="w"> </span><span class="m">192</span>.168.1.202<span class="w"> </span><span class="m">111</span>.82<span class="w"> </span>KB<span class="w"> </span><span class="m">256</span><span class="w"> </span><span class="m">33</span>.1%<span class="w"> </span>8d5ed9f4-7764-4dbd-bad8-43fddce94b7c<span class="w"> </span>B1
|
||
UN<span class="w"> </span><span class="m">192</span>.168.1.203<span class="w"> </span><span class="m">114</span>.82<span class="w"> </span>KB<span class="w"> </span><span class="m">256</span><span class="w"> </span><span class="m">33</span>.3%<span class="w"> </span>8d5ed9f4-7764-4dbd-bad8-43fddce94b7c<span class="w"> </span>C1
|
||
</pre></div>
|
||
</div>
|
||
<p>All nodes holds 100% of the data.
|
||
If needed to add a single node to the cluster (scale out), the cluster will become imbalance.
|
||
Because the single additional node will split the tokens only with the existing node in the same AZ.</p>
|
||
<div class="admonition note">
|
||
<p class="admonition-title">Note</p>
|
||
<p>This is only an example, if having more nodes or different RF the number of nodes may be different.</p>
|
||
</div>
|
||
<p>The token distribution will be:</p>
|
||
<div class="highlight-shell notranslate"><div class="highlight"><pre><span></span>AZ<span class="w"> </span>A1<span class="w"> </span>node<span class="w"> </span>A:<span class="w"> </span><span class="m">100</span>%<span class="w"> </span>of<span class="w"> </span>the<span class="w"> </span>data
|
||
AZ<span class="w"> </span>B1<span class="w"> </span>node<span class="w"> </span>B:<span class="w"> </span><span class="m">100</span>%<span class="w"> </span>of<span class="w"> </span>the<span class="w"> </span>data
|
||
AZ<span class="w"> </span>C1<span class="w"> </span>node<span class="w"> </span>C:<span class="w"> </span><span class="m">50</span>%<span class="w"> </span>of<span class="w"> </span>the<span class="w"> </span>data
|
||
AZ<span class="w"> </span>C1<span class="w"> </span>node<span class="w"> </span>D:<span class="w"> </span><span class="m">50</span>%<span class="w"> </span>of<span class="w"> </span>the<span class="w"> </span>data
|
||
</pre></div>
|
||
</div>
|
||
<p>The solution is to add a node in each AZ.</p>
|
||
<div class="highlight-shell notranslate"><div class="highlight"><pre><span></span>Datacenter:<span class="w"> </span>DC1
|
||
<span class="nv">Status</span><span class="o">=</span>Up/Down
|
||
<span class="nv">State</span><span class="o">=</span>Normal/Leaving/Joining/Moving
|
||
--<span class="w"> </span>Address<span class="w"> </span>Load<span class="w"> </span>Tokens<span class="w"> </span>Owns<span class="w"> </span><span class="o">(</span>effective<span class="o">)</span><span class="w"> </span>Host<span class="w"> </span>ID<span class="w"> </span>Rack
|
||
UN<span class="w"> </span><span class="m">192</span>.168.1.201<span class="w"> </span><span class="m">118</span>.82<span class="w"> </span>KB<span class="w"> </span><span class="m">256</span><span class="w"> </span><span class="m">16</span>.6%<span class="w"> </span>8d5ed9f4-7764-4dbd-bad8-43fddce94b7c<span class="w"> </span>A1
|
||
UN<span class="w"> </span><span class="m">192</span>.168.1.202<span class="w"> </span><span class="m">111</span>.82<span class="w"> </span>KB<span class="w"> </span><span class="m">256</span><span class="w"> </span><span class="m">16</span>.1%<span class="w"> </span>8d5ed9f4-7764-4dbd-bad8-43fddce94b7c<span class="w"> </span>B1
|
||
UN<span class="w"> </span><span class="m">192</span>.168.1.203<span class="w"> </span><span class="m">114</span>.82<span class="w"> </span>KB<span class="w"> </span><span class="m">256</span><span class="w"> </span><span class="m">16</span>.3%<span class="w"> </span>8d5ed9f4-7764-4dbd-bad8-43fddce94b7c<span class="w"> </span>C1
|
||
UN<span class="w"> </span><span class="m">192</span>.168.1.204<span class="w"> </span><span class="m">118</span>.82<span class="w"> </span>KB<span class="w"> </span><span class="m">256</span><span class="w"> </span><span class="m">16</span>.6%<span class="w"> </span>8d5ed9f4-7764-4dbd-bad8-43fddce94b7c<span class="w"> </span>A1
|
||
UN<span class="w"> </span><span class="m">192</span>.168.1.205<span class="w"> </span><span class="m">111</span>.82<span class="w"> </span>KB<span class="w"> </span><span class="m">256</span><span class="w"> </span><span class="m">16</span>.1%<span class="w"> </span>8d5ed9f4-7764-4dbd-bad8-43fddce94b7c<span class="w"> </span>B1
|
||
UN<span class="w"> </span><span class="m">192</span>.168.1.206<span class="w"> </span><span class="m">114</span>.82<span class="w"> </span>KB<span class="w"> </span><span class="m">256</span><span class="w"> </span><span class="m">16</span>.3%<span class="w"> </span>8d5ed9f4-7764-4dbd-bad8-43fddce94b7c<span class="w"> </span>C1
|
||
</pre></div>
|
||
</div>
|
||
</section>
|
||
</section>
|
||
<section id="more-info">
|
||
<h2>More info<a class="headerlink" href="#more-info" title="Link to this heading">¶</a></h2>
|
||
<section id="where-can-i-ask-a-question-not-covered-here">
|
||
<h3>Where can I ask a question not covered here?<a class="headerlink" href="#where-can-i-ask-a-question-not-covered-here" title="Link to this heading">¶</a></h3>
|
||
<ul class="simple">
|
||
<li><p><a class="reference external" href="https://forum.scylladb.com">ScyllaDB Community Forum</a>: Discuss using ScyllaDB and developing client applications.</p></li>
|
||
<li><p><a class="reference external" href="https://groups.google.com/d/forum/scylladb-dev">scylladb-dev</a>: Discuss the development of ScyllaDB itself.</p></li>
|
||
</ul>
|
||
</section>
|
||
<section id="i-deleted-data-from-scylladb-but-disk-usage-stays-the-same-why">
|
||
<h3>I deleted data from ScyllaDB, but disk usage stays the same. Why?<a class="headerlink" href="#i-deleted-data-from-scylladb-but-disk-usage-stays-the-same-why" title="Link to this heading">¶</a></h3>
|
||
<p>Data you write to ScyllaDB gets persisted to SSTables. Since SSTables are immutable, the data can’t actually be removed
|
||
when you perform a delete, instead, a marker (also called a “tombstone”) is written to indicate the value’s new status.
|
||
Never fear though, on the first compaction that occurs between the data and the tombstone, the data will be expunged
|
||
completely and the corresponding disk space recovered.</p>
|
||
</section>
|
||
<section id="is-raid0-required-for-scylladb-why">
|
||
<span id="faq-raid0-required"></span><h3>Is RAID0 required for ScyllaDB? Why?<a class="headerlink" href="#is-raid0-required-for-scylladb-why" title="Link to this heading">¶</a></h3>
|
||
<p>No, it is not required, but it is highly recommended when using ScyllaDB with more than one drive. ScyllaDB requires one drive for its data file and one drive for commit log (can be the same). If you want to take advantage of more than one drive, the easiest way to do so is set RAID0 (striped) across all of them. If you choose, scylla_setup will setup RAID0 for you on your selected drive, as well as XFS file system (recommended).
|
||
Similarly, ScyllaDB AMI on EC2 will automatically mount all available SSD drives in RAID0.</p>
|
||
</section>
|
||
<section id="should-i-use-raid-for-replications-such-as-raid1-raid4-or-higher">
|
||
<h3>Should I use RAID for replications, such as RAID1, RAID4 or higher?<a class="headerlink" href="#should-i-use-raid-for-replications-such-as-raid1-raid4-or-higher" title="Link to this heading">¶</a></h3>
|
||
<p>You can, but it is not recommended. ScyllaDB <a class="reference internal" href="architecture/ringarchitecture/index.html"><span class="doc">clustering architecture</span></a> already provides data replication across nodes and DCs.
|
||
Adding another layer of replication in each node is redundant, slows down I/O operation and reduces available storage.
|
||
Want a higher level of replication?
|
||
Increase the Replication Factor (RF) of <a class="reference internal" href="cql/ddl.html"><span class="doc">relevant Keyspaces</span></a>.</p>
|
||
</section>
|
||
<section id="can-i-use-jbod-and-not-use-raid0">
|
||
<h3>Can I use JBOD and not use RAID0?<a class="headerlink" href="#can-i-use-jbod-and-not-use-raid0" title="Link to this heading">¶</a></h3>
|
||
<p><a class="reference internal" href="reference/glossary.html#term-JBOD"><span class="xref std std-term">JBOD</span></a> is not supported by ScyllaDB.</p>
|
||
<p><abbr title="Just a Bunch Of Disks">JBOD</abbr> may be a reasonable solution for Cassandra because it rebuilds nodes very slowly. As this is not an issue for ScyllaDB, it’s more efficient to use RAID.</p>
|
||
<p>Explanation: There are two types of deployment when multiple disks exist. In the JBOD case, each disk is an isolated filesystem. I/O isn’t stripped and thus performance can be slower than that of RAID. In addition, as the free space isn’t shared, a single disk can be full while the others are available.</p>
|
||
<p>The benefit of JBOD vs RAID is that it isolates failures to individual disk and not the entire node.
|
||
However, ScyllaDB rebuilds nodes quickly and thus it is not an issue when rebuilding an entire node.</p>
|
||
<p>As a result, it is much more advantageous to use RAID with ScyllaDB</p>
|
||
</section>
|
||
<section id="is-nodetool-repair-a-local-one-node-operation-or-a-global-full-cluster-operation">
|
||
<h3>Is <code class="docutils literal notranslate"><span class="pre">Nodetool</span> <span class="pre">Repair</span></code> a Local (One Node) Operation or a Global (Full Cluster) Operation?<a class="headerlink" href="#is-nodetool-repair-a-local-one-node-operation-or-a-global-full-cluster-operation" title="Link to this heading">¶</a></h3>
|
||
<p>When running <a class="reference internal" href="operating-scylla/nodetool-commands/repair.html"><span class="doc">nodetool repair</span></a> on a node, it performs a repair on every token range this node owns; this will also repair other nodes that share the same range.</p>
|
||
<p>If you wish to repair the entire cluster, it is recommended to run <code class="docutils literal notranslate"><span class="pre">nodetool</span> <span class="pre">repair</span> <span class="pre">-pr</span></code> on each node in the cluster, sequentially, or use the <a class="reference external" href="https://manager.docs.scylladb.com/">ScyllaDB Manager</a>.</p>
|
||
</section>
|
||
<section id="how-can-i-change-the-maximum-number-of-in-restrictions">
|
||
<h3>How can I change the maximum number of IN restrictions?<a class="headerlink" href="#how-can-i-change-the-maximum-number-of-in-restrictions" title="Link to this heading">¶</a></h3>
|
||
<p>You can restrict the number of items in the IN clause with the following options:</p>
|
||
<ul class="simple">
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">--max-partition-key-restrictions-per-query</span></code> - Specifies the maximum number of distinct partition keys restrictions per query. This limit places a bound
|
||
on the size of IN tuples, especially when multiple partition key columns have IN restrictions. The default is <code class="docutils literal notranslate"><span class="pre">100</span></code>.</p></li>
|
||
<li><p><code class="docutils literal notranslate"><span class="pre">--max-clustering-key-restrictions-per-query</span></code> - Specifies the maximum number of distinct clustering keys restrictions per query. This limit
|
||
places a bound on the size of IN tuples, especially when multiple clustering key columns have IN restrictions. The default is <code class="docutils literal notranslate"><span class="pre">100</span></code>.</p></li>
|
||
</ul>
|
||
<div class="admonition warning">
|
||
<p class="admonition-title">Warning</p>
|
||
<p>We recommend that you use these options with caution. Changing the maximum number of IN restrictions to more than 100 may result in server instability.</p>
|
||
</div>
|
||
<p>The options can be configured on the command line, passed with <code class="docutils literal notranslate"><span class="pre">SCYLLA_ARGS</span></code> in <code class="docutils literal notranslate"><span class="pre">/etc/default/scylla-server</span></code> or <code class="docutils literal notranslate"><span class="pre">/etc/sysconfig/scylla-server</span></code>,
|
||
or added to your <code class="docutils literal notranslate"><span class="pre">scylla.yaml</span></code> (see <a class="reference internal" href="operating-scylla/admin.html"><span class="doc">ScyllaDB Configuration</span></a>).</p>
|
||
</section>
|
||
<section id="can-i-change-the-coredump-mount-point">
|
||
<h3>Can I change the coredump mount point?<a class="headerlink" href="#can-i-change-the-coredump-mount-point" title="Link to this heading">¶</a></h3>
|
||
<p>Yes, by edit <code class="docutils literal notranslate"><span class="pre">sysctl.d</span></code>.</p>
|
||
<p>Procedure</p>
|
||
<ol class="arabic simple">
|
||
<li><p>Create <code class="docutils literal notranslate"><span class="pre">/etc/sysctl.d/99-scylla-coredump.conf</span></code> (this file exists by default in ScyllaDB AMI).</p></li>
|
||
<li><p>Open the <code class="docutils literal notranslate"><span class="pre">99-scylla-coredump.conf</span></code> file.</p></li>
|
||
<li><p>Add the following line <code class="docutils literal notranslate"><span class="pre">kernel.core_pattern=|/<path>/<coredump_directory></span> <span class="pre">%p</span> <span class="pre">%u</span> <span class="pre">%g</span> <span class="pre">%s</span> <span class="pre">%t</span> <span class="pre">%e"</span></code></p></li>
|
||
</ol>
|
||
<p>For example:</p>
|
||
<div class="highlight-shell notranslate"><div class="highlight"><pre><span></span>kernel.core_pattern<span class="o">=</span><span class="p">|</span>/home/centos/core/<span class="w"> </span>%p<span class="w"> </span>%u<span class="w"> </span>%g<span class="w"> </span>%s<span class="w"> </span>%t<span class="w"> </span>%e<span class="s2">"</span>
|
||
</pre></div>
|
||
</div>
|
||
<ol class="arabic simple" start="4">
|
||
<li><p>Run <code class="docutils literal notranslate"><span class="pre">sysctl</span> <span class="pre">-p</span> <span class="pre">/etc/sysctl.d/99-scylla-coredump.conf</span></code></p></li>
|
||
</ol>
|
||
</section>
|
||
</section>
|
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|
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<li><a class="reference internal" href="#scylladb-is-using-all-of-my-memory-why-is-that-what-if-the-server-runs-out-of-memory">ScyllaDB is using all of my memory! Why is that? What if the server runs out of memory?</a></li>
|
||
<li><a class="reference internal" href="#can-i-limit-scylladb-to-use-less-cpu-and-memory">Can I limit ScyllaDB to use less CPU and memory?</a></li>
|
||
<li><a class="reference internal" href="#what-are-some-of-the-techniques-scylladb-uses-to-achieve-its-performance">What are some of the techniques ScyllaDB uses to achieve its performance?</a></li>
|
||
<li><a class="reference internal" href="#i-thought-that-scylladb-s-underlying-seastar-framework-uses-one-thread-per-core-but-i-see-more-than-two-threads-per-core-why">I thought that ScyllaDB’s underlying Seastar framework uses one thread per core, but I see more than two threads per core. Why?</a></li>
|
||
<li><a class="reference internal" href="#im-seeing-x-compaction-running-in-parallel-on-a-single-scylladb-node-is-it-normal">I’m seeing X compaction running in parallel on a single ScyllaDB node. Is it normal?</a></li>
|
||
<li><a class="reference internal" href="#setting-io-conf-configuration-for-hdd-storage">Setting io.conf configuration for HDD storage</a></li>
|
||
<li><a class="reference internal" href="#how-many-connections-is-it-recommended-to-open-from-each-scylladb-client-application">How many connections is it recommended to open from each ScyllaDB client application?</a></li>
|
||
<li><a class="reference internal" href="#do-i-need-to-configure-swap-on-a-scylladb-node">Do I need to configure <code class="docutils literal notranslate"><span class="pre">swap</span></code> on a ScyllaDB node?</a></li>
|
||
<li><a class="reference internal" href="#my-query-does-not-return-any-or-some-of-the-data-what-happened">My query does not return any or some of the data? What happened?</a></li>
|
||
<li><a class="reference internal" href="#desc-schema-shows-that-i-am-using-many-materialized-views-mvs-when-i-know-i-only-added-secondary-indexes-si-why-are-there-mvs-in-my-schema">DESC SCHEMA shows that I am using many materialized views (MVs) when I know I only added Secondary Indexes (SI). Why are there MVs in my schema?</a></li>
|
||
<li><a class="reference internal" href="#using-the-java-driver-simplestatements-are-slow-why-does-this-happen">Using the Java driver SimpleStatements are slow. Why does this happen?</a></li>
|
||
</ul>
|
||
</li>
|
||
<li><a class="reference internal" href="#disk-space">Disk Space</a><ul>
|
||
<li><a class="reference internal" href="#dropping-a-table-does-not-reduce-storage-used-by-scylladb-how-can-i-clean-the-disk-from-dropped-tables">Dropping a table does not reduce storage used by ScyllaDB, how can I clean the disk from dropped tables?</a></li>
|
||
</ul>
|
||
</li>
|
||
<li><a class="reference internal" href="#features">Features</a><ul>
|
||
<li><a class="reference internal" href="#i-want-to-try-out-new-features-how-do-i-enable-experimental-mode">I want to try out new features. How do I enable experimental mode?</a></li>
|
||
<li><a class="reference internal" href="#how-do-i-check-the-current-version-of-scylladb-that-i-am-running">How do I check the current version of ScyllaDB that I am running?</a></li>
|
||
<li><a class="reference internal" href="#i-am-upgrading-my-nodes-to-a-version-that-uses-a-newer-sstable-format-when-will-the-nodes-start-using-the-new-sstable-format">I am upgrading my nodes to a version that uses a newer SSTable format, when will the nodes start using the new SSTable format?</a></li>
|
||
</ul>
|
||
</li>
|
||
<li><a class="reference internal" href="#docker">Docker</a><ul>
|
||
<li><a class="reference internal" href="#what-if-i-get-an-error-when-connecting-an-application-to-a-scylladb-cluster-in-docker">What if I get an error when connecting an application to a ScyllaDB cluster in Docker?</a></li>
|
||
</ul>
|
||
</li>
|
||
<li><a class="reference internal" href="#installation">Installation</a><ul>
|
||
<li><a class="reference internal" href="#can-i-install-scylladb-on-an-apache-cassandra-server">Can I install ScyllaDB on an Apache Cassandra server?</a></li>
|
||
<li><a class="reference internal" href="#can-i-install-or-upgrade-to-a-patch-release-other-than-latest-on-debian-or-ubuntu">Can I install or upgrade to a patch release other than latest on Debian or Ubuntu?</a></li>
|
||
<li><a class="reference internal" href="#which-snitch-or-replication-strategy-should-i-use">Which snitch or replication strategy should I use?</a></li>
|
||
<li><a class="reference internal" href="#can-i-change-the-replication-factor-a-keyspace-on-a-live-cluster">Can I change the replication factor (a keyspace) on a live cluster?</a></li>
|
||
<li><a class="reference internal" href="#why-can-t-i-set-listen-address-to-listen-to-0-0-0-0-all-my-addresses">Why can’t I set <code class="docutils literal notranslate"><span class="pre">listen_address</span></code> to listen to 0.0.0.0 (all my addresses)?</a></li>
|
||
<li><a class="reference internal" href="#what-is-the-best-scenario-to-add-a-node-to-a-multi-availability-zone-az">What is the best scenario to add a node to a multi availability zone (AZ)?</a></li>
|
||
</ul>
|
||
</li>
|
||
<li><a class="reference internal" href="#more-info">More info</a><ul>
|
||
<li><a class="reference internal" href="#where-can-i-ask-a-question-not-covered-here">Where can I ask a question not covered here?</a></li>
|
||
<li><a class="reference internal" href="#i-deleted-data-from-scylladb-but-disk-usage-stays-the-same-why">I deleted data from ScyllaDB, but disk usage stays the same. Why?</a></li>
|
||
<li><a class="reference internal" href="#is-raid0-required-for-scylladb-why">Is RAID0 required for ScyllaDB? Why?</a></li>
|
||
<li><a class="reference internal" href="#should-i-use-raid-for-replications-such-as-raid1-raid4-or-higher">Should I use RAID for replications, such as RAID1, RAID4 or higher?</a></li>
|
||
<li><a class="reference internal" href="#can-i-use-jbod-and-not-use-raid0">Can I use JBOD and not use RAID0?</a></li>
|
||
<li><a class="reference internal" href="#is-nodetool-repair-a-local-one-node-operation-or-a-global-full-cluster-operation">Is <code class="docutils literal notranslate"><span class="pre">Nodetool</span> <span class="pre">Repair</span></code> a Local (One Node) Operation or a Global (Full Cluster) Operation?</a></li>
|
||
<li><a class="reference internal" href="#how-can-i-change-the-maximum-number-of-in-restrictions">How can I change the maximum number of IN restrictions?</a></li>
|
||
<li><a class="reference internal" href="#can-i-change-the-coredump-mount-point">Can I change the coredump mount point?</a></li>
|
||
</ul>
|
||
</li>
|
||
</ul>
|
||
</li>
|
||
</ul>
|
||
|
||
</div>
|
||
|
||
</div>
|
||
</div>
|
||
</div>
|
||
|
||
</div>
|
||
<div class="sidebar-left large-order-1">
|
||
|
||
|
||
<div id="side-nav" class="side-nav custom-scroll-bar" data-closable data-toggler=".show">
|
||
<button class="collapsible-button">
|
||
<i class="icon-docs-menu-collapse"></i>
|
||
</button>
|
||
<div class="side-nav-content custom-scroll-bar">
|
||
<div class="side-nav__title">
|
||
<a href="index.html">ScyllaDB Open Source</a>
|
||
</div>
|
||
<div class="side-nav__search">
|
||
|
||
<biel-search-button
|
||
project="ddfdo8m94k"
|
||
button-style="rounded"
|
||
hide-filters="false"
|
||
hide-ctrl-k="true"
|
||
header-title="ScyllaDB chatbot (beta)"
|
||
modal-position="top-center">
|
||
Search
|
||
</biel-search-button>
|
||
|
||
<biel-button class="side-nav__ask-ai" project="ddfdo8m94k"
|
||
header-title="ScyllaDB chatbot (beta)"
|
||
button-position="default"
|
||
modal-position="sidebar-right"
|
||
button-style="dark">
|
||
Ask AI
|
||
</biel-button>
|
||
|
||
|
||
</div>
|
||
<div class="side-nav__versions"><ul class="dropdown menu scylla-dropdown scylla-dropdown--versions" data-dropdown-menu>
|
||
<li class="scylla-dropdown__item">
|
||
<a class="scylla-dropdown__title" href="#">
|
||
|
||
6.2
|
||
|
||
<i class="chevron icon-docs-chevron-right"></i>
|
||
</a>
|
||
<ul class="menu scylla-dropdown__content">
|
||
|
||
|
||
<li>
|
||
<a href="faq.html">6.2</a>
|
||
</li>
|
||
|
||
|
||
|
||
<li>
|
||
<a href="../branch-6.1/faq.html">6.1</a>
|
||
</li>
|
||
|
||
|
||
|
||
<li>
|
||
<a href="../branch-6.0/faq.html">6.0</a>
|
||
</li>
|
||
|
||
|
||
|
||
<li>
|
||
<a href="../branch-5.4/faq.html">5.4</a>
|
||
</li>
|
||
|
||
|
||
|
||
<li>
|
||
<a href="../branch-5.2/faq.html">5.2</a>
|
||
</li>
|
||
|
||
|
||
|
||
<li>
|
||
<a href="../branch-5.1/faq.html">5.1</a>
|
||
</li>
|
||
|
||
|
||
|
||
</ul>
|
||
</li>
|
||
</ul></div>
|
||
<div class="side-nav__content">
|
||
<ul class="current">
|
||
<li class="toctree-l1 has-children"><a class="reference internal" href="getting-started/index.html">Getting Started</a><input class="toctree-checkbox" id="toctree-checkbox-1" name="toctree-checkbox-1" type="checkbox"/><label for="toctree-checkbox-1"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
|
||
<li class="toctree-l2 has-children"><a class="reference internal" href="getting-started/install-scylla/index.html">Install ScyllaDB</a><input class="toctree-checkbox" id="toctree-checkbox-2" name="toctree-checkbox-2" type="checkbox"/><label for="toctree-checkbox-2"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
|
||
<li class="toctree-l3"><a class="reference internal" href="getting-started/install-scylla/launch-on-aws.html">Launch ScyllaDB on AWS</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="getting-started/install-scylla/launch-on-gcp.html">Launch ScyllaDB on GCP</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="getting-started/install-scylla/launch-on-azure.html">Launch ScyllaDB on Azure</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="getting-started/installation-common/scylla-web-installer.html">ScyllaDB Web Installer for Linux</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="getting-started/install-scylla/install-on-linux.html">Install ScyllaDB Linux Packages</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="getting-started/install-scylla/install-jmx.html">Install scylla-jmx Package</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="getting-started/install-scylla/run-in-docker.html">Run ScyllaDB in Docker</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="getting-started/installation-common/unified-installer.html">Install ScyllaDB Without root Privileges</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="getting-started/installation-common/air-gapped-install.html">Air-gapped Server Installation</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="getting-started/installation-common/disable-housekeeping.html">ScyllaDB Housekeeping and how to disable it</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="getting-started/installation-common/dev-mod.html">ScyllaDB Developer Mode</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l2"><a class="reference internal" href="getting-started/configure.html">Configure ScyllaDB</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="getting-started/config-commands.html">ScyllaDB Configuration Reference</a></li>
|
||
<li class="toctree-l2 has-children"><a class="reference internal" href="getting-started/requirements.html">ScyllaDB Requirements</a><input class="toctree-checkbox" id="toctree-checkbox-3" name="toctree-checkbox-3" type="checkbox"/><label for="toctree-checkbox-3"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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<li class="toctree-l3"><a class="reference internal" href="getting-started/system-requirements.html">System Requirements</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="getting-started/os-support.html">OS Support by Linux Distributions and Version</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="getting-started/cloud-instance-recommendations.html">Cloud Instance Recommendations</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="getting-started/scylla-in-a-shared-environment.html">ScyllaDB in a Shared Environment</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l2 has-children"><a class="reference internal" href="using-scylla/migrate-scylla.html">Migrate to ScyllaDB</a><input class="toctree-checkbox" id="toctree-checkbox-4" name="toctree-checkbox-4" type="checkbox"/><label for="toctree-checkbox-4"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/procedures/cassandra-to-scylla-migration-process.html">Migration Process from Cassandra to ScyllaDB</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="using-scylla/cassandra-compatibility.html">ScyllaDB and Apache Cassandra Compatibility</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="using-scylla/mig-tool-review.html">Migration Tools Overview</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l2 has-children"><a class="reference internal" href="using-scylla/integrations/index.html">Integration Solutions</a><input class="toctree-checkbox" id="toctree-checkbox-5" name="toctree-checkbox-5" type="checkbox"/><label for="toctree-checkbox-5"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
|
||
<li class="toctree-l3"><a class="reference internal" href="using-scylla/integrations/integration-spark.html">Integrate ScyllaDB with Spark</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="using-scylla/integrations/integration-kairos.html">Integrate ScyllaDB with KairosDB</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="using-scylla/integrations/integration-presto.html">Integrate ScyllaDB with Presto</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="using-scylla/integrations/integration-elasticsearch.html">Integrate ScyllaDB with Elasticsearch</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="using-scylla/integrations/integration-k8.html">Integrate ScyllaDB with Kubernetes</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="using-scylla/integrations/integration-janus.html">Integrate ScyllaDB with the JanusGraph Graph Data System</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="using-scylla/integrations/integration-datadog.html">Integrate ScyllaDB with DataDog</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="using-scylla/integrations/integration-kafka.html">Integrate ScyllaDB with Kafka</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="using-scylla/integrations/integration-iota.html">Integrate ScyllaDB with IOTA Chronicle</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="using-scylla/integrations/integration-spring.html">Integrate ScyllaDB with Spring</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="using-scylla/integrations/sink-kafka-connector.html">Shard-Aware Kafka Connector for ScyllaDB</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="using-scylla/integrations/integration-ansible.html">Install ScyllaDB with Ansible</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="using-scylla/integrations/integration-databricks.html">Integrate ScyllaDB with Databricks</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="using-scylla/integrations/integration-jaeger.html">Integrate ScyllaDB with Jaeger Server</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="using-scylla/integrations/integration-mindsdb.html">Integrate ScyllaDB with MindsDB</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l2"><a class="reference internal" href="getting-started/tutorials.html">Tutorials</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l1 has-children"><a class="reference internal" href="operating-scylla/index.html">ScyllaDB for Administrators</a><input class="toctree-checkbox" id="toctree-checkbox-6" name="toctree-checkbox-6" type="checkbox"/><label for="toctree-checkbox-6"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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||
<li class="toctree-l2"><a class="reference internal" href="operating-scylla/admin.html">Administration Guide</a></li>
|
||
<li class="toctree-l2 has-children"><a class="reference internal" href="operating-scylla/procedures/index.html">Procedures</a><input class="toctree-checkbox" id="toctree-checkbox-7" name="toctree-checkbox-7" type="checkbox"/><label for="toctree-checkbox-7"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/procedures/cluster-management/index.html">Cluster Management</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/procedures/backup-restore/index.html">Backup & Restore</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/procedures/config-change/index.html">Change Configuration</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/procedures/maintenance/index.html">Maintenance</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/procedures/tips/index.html">Best Practices</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/benchmarking-scylla.html">Benchmarking ScyllaDB</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/procedures/cassandra-to-scylla-migration-process.html">Migrate from Cassandra to ScyllaDB</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="getting-started/installation-common/disable-housekeeping.html">Disable Housekeeping</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l2 has-children"><a class="reference internal" href="operating-scylla/security/index.html">Security</a><input class="toctree-checkbox" id="toctree-checkbox-8" name="toctree-checkbox-8" type="checkbox"/><label for="toctree-checkbox-8"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/security/security-checklist.html">ScyllaDB Security Checklist</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/security/authentication.html">Enable Authentication</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/security/runtime-authentication.html">Enable and Disable Authentication Without Downtime</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/security/create-superuser.html">Creating a Custom Superuser</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/security/gen-cqlsh-file.html">Generate a cqlshrc File</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="troubleshooting/password-reset.html">Reset Authenticator Password</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/security/enable-authorization.html">Enable Authorization</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/security/authorization.html">Grant Authorization CQL Reference</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/security/certificate-authentication.html">Certificate-based Authentication</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/security/rbac-usecase.html">Role Based Access Control (RBAC)</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/security/client-node-encryption.html">Encryption: Data in Transit Client to Node</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/security/node-node-encryption.html">Encryption: Data in Transit Node to Node</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/security/generate-certificate.html">Generating a self-signed Certificate Chain Using openssl</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/security/saslauthd.html">Configure SaslauthdAuthenticator</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l2 has-children"><a class="reference internal" href="operating-scylla/admin-tools/index.html">Admin Tools</a><input class="toctree-checkbox" id="toctree-checkbox-9" name="toctree-checkbox-9" type="checkbox"/><label for="toctree-checkbox-9"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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<li class="toctree-l3"><a class="reference internal" href="operating-scylla/nodetool.html">Nodetool Reference</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="cql/cqlsh.html">CQLSh</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/rest.html">Admin REST API</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="using-scylla/tracing.html">Tracing</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/admin-tools/scylla-sstable.html">ScyllaDB SStable</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/admin-tools/scylla-types.html">ScyllaDB Types</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/admin-tools/sstableloader.html">SSTableLoader</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/admin-tools/cassandra-stress.html">cassandra-stress</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/admin-tools/sstabledump.html">SSTabledump</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/admin-tools/sstablemetadata.html">SSTableMetadata</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="getting-started/logging.html">ScyllaDB Logs</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/admin-tools/perftune.html">Seastar Perftune</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/admin-tools/virtual-tables.html">Virtual Tables</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/admin-tools/select-from-mutation-fragments.html">Reading mutation fragments</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/admin-tools/maintenance-socket.html">Maintenance socket</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/admin-tools/maintenance-mode.html">Maintenance mode</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/admin-tools/task-manager.html">Task manager</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l2"><a class="reference external" href="https://monitoring.docs.scylladb.com/">ScyllaDB Monitoring Stack</a></li>
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<li class="toctree-l2"><a class="reference external" href="https://operator.docs.scylladb.com/">ScyllaDB Operator</a></li>
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<li class="toctree-l2"><a class="reference external" href="https://manager.docs.scylladb.com/">ScyllaDB Manager</a></li>
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<li class="toctree-l2 has-children"><a class="reference internal" href="upgrade/index.html">Upgrade Procedures</a><input class="toctree-checkbox" id="toctree-checkbox-10" name="toctree-checkbox-10" type="checkbox"/><label for="toctree-checkbox-10"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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<li class="toctree-l3"><a class="reference internal" href="upgrade/scylladb-versioning.html">ScyllaDB Versioning</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="upgrade/upgrade-opensource/index.html">ScyllaDB Open Source Upgrade</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="upgrade/upgrade-to-enterprise/index.html">ScyllaDB Open Source to ScyllaDB Enterprise Upgrade</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="upgrade/ami-upgrade.html">ScyllaDB Image</a></li>
|
||
<li class="toctree-l3"><a class="reference external" href="https://enterprise.docs.scylladb.com/stable/upgrade/upgrade-enterprise/index.html">ScyllaDB Enterprise</a></li>
|
||
</ul>
|
||
</li>
|
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<li class="toctree-l2 has-children"><a class="reference internal" href="operating-scylla/system-configuration/index.html">System Configuration</a><input class="toctree-checkbox" id="toctree-checkbox-11" name="toctree-checkbox-11" type="checkbox"/><label for="toctree-checkbox-11"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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<li class="toctree-l3"><a class="reference internal" href="getting-started/system-configuration.html">System Configuration Guide</a></li>
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||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/admin.html">scylla.yaml</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/system-configuration/snitch.html">ScyllaDB Snitches</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l2"><a class="reference internal" href="operating-scylla/benchmarking-scylla.html">Benchmarking ScyllaDB</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="operating-scylla/diagnostics.html">ScyllaDB Diagnostic Tools</a></li>
|
||
</ul>
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</li>
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<li class="toctree-l1 has-children"><a class="reference internal" href="using-scylla/index.html">ScyllaDB for Developers</a><input class="toctree-checkbox" id="toctree-checkbox-12" name="toctree-checkbox-12" type="checkbox"/><label for="toctree-checkbox-12"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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<li class="toctree-l2"><a class="reference external" href="https://docs.scylladb.com/stable/get-started/develop-with-scylladb/index.html">Develop with ScyllaDB</a></li>
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<li class="toctree-l2"><a class="reference external" href="https://docs.scylladb.com/stable/get-started/develop-with-scylladb/tutorials-example-projects.html">Tutorials and Example Projects</a></li>
|
||
<li class="toctree-l2"><a class="reference external" href="https://docs.scylladb.com/stable/get-started/learn-resources/index.html">Learn to Use ScyllaDB</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="using-scylla/alternator/index.html">ScyllaDB Alternator</a></li>
|
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<li class="toctree-l2 has-children"><a class="reference internal" href="using-scylla/drivers/index.html">ScyllaDB Drivers</a><input class="toctree-checkbox" id="toctree-checkbox-13" name="toctree-checkbox-13" type="checkbox"/><label for="toctree-checkbox-13"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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<li class="toctree-l3"><a class="reference internal" href="using-scylla/drivers/cql-drivers/index.html">ScyllaDB CQL Drivers</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="using-scylla/drivers/dynamo-drivers/index.html">ScyllaDB DynamoDB Drivers</a></li>
|
||
</ul>
|
||
</li>
|
||
</ul>
|
||
</li>
|
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<li class="toctree-l1 has-children"><a class="reference internal" href="cql/index.html">CQL Reference</a><input class="toctree-checkbox" id="toctree-checkbox-14" name="toctree-checkbox-14" type="checkbox"/><label for="toctree-checkbox-14"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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<li class="toctree-l2"><a class="reference internal" href="cql/cqlsh.html">CQLSh: the CQL shell</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="cql/appendices.html">Appendices</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="cql/compaction.html">Compaction</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="cql/consistency.html">Consistency Levels</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="cql/consistency-calculator.html">Consistency Level Calculator</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="cql/ddl.html">Data Definition</a></li>
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<li class="toctree-l2 has-children"><a class="reference internal" href="cql/dml.html">Data Manipulation</a><input class="toctree-checkbox" id="toctree-checkbox-15" name="toctree-checkbox-15" type="checkbox"/><label for="toctree-checkbox-15"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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<li class="toctree-l3"><a class="reference internal" href="cql/dml/select.html">SELECT</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="cql/dml/insert.html">INSERT</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="cql/dml/update.html">UPDATE</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="cql/dml/delete.html">DELETE</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="cql/dml/batch.html">BATCH</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l2"><a class="reference internal" href="cql/types.html">Data Types</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="cql/definitions.html">Definitions</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="cql/secondary-indexes.html">Global Secondary Indexes</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="cql/time-to-live.html">Expiring Data with Time to Live (TTL)</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="cql/functions.html">Functions</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="cql/wasm.html">Wasm support for user-defined functions</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="cql/json.html">JSON Support</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="cql/mv.html">Materialized Views</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="cql/non-reserved-keywords.html">Non-Reserved CQL Keywords</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="cql/reserved-keywords.html">Reserved CQL Keywords</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="cql/service-levels.html">Service Levels</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="cql/cql-extensions.html">ScyllaDB CQL Extensions</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l1 has-children"><a class="reference internal" href="alternator/alternator.html">Alternator: DynamoDB API in Scylla</a><input class="toctree-checkbox" id="toctree-checkbox-16" name="toctree-checkbox-16" type="checkbox"/><label for="toctree-checkbox-16"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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<li class="toctree-l2"><a class="reference internal" href="alternator/getting-started.html">Getting Started With ScyllaDB Alternator</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="alternator/compatibility.html">ScyllaDB Alternator for DynamoDB users</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l1 has-children"><a class="reference internal" href="features/index.html">Features</a><input class="toctree-checkbox" id="toctree-checkbox-17" name="toctree-checkbox-17" type="checkbox"/><label for="toctree-checkbox-17"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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||
<li class="toctree-l2"><a class="reference internal" href="features/lwt.html">Lightweight Transactions</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="features/secondary-indexes.html">Global Secondary Indexes</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="features/local-secondary-indexes.html">Local Secondary Indexes</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="features/materialized-views.html">Materialized Views</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="features/counters.html">Counters</a></li>
|
||
<li class="toctree-l2 has-children"><a class="reference internal" href="features/cdc/index.html">Change Data Capture</a><input class="toctree-checkbox" id="toctree-checkbox-18" name="toctree-checkbox-18" type="checkbox"/><label for="toctree-checkbox-18"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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<li class="toctree-l3"><a class="reference internal" href="features/cdc/cdc-intro.html">CDC Overview</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="features/cdc/cdc-log-table.html">The CDC Log Table</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="features/cdc/cdc-basic-operations.html">Basic operations in CDC</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="features/cdc/cdc-streams.html">CDC Streams</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="features/cdc/cdc-stream-generations.html">CDC Stream Generations</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="features/cdc/cdc-querying-streams.html">Querying CDC Streams</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="features/cdc/cdc-advanced-types.html">Advanced column types</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="features/cdc/cdc-preimages.html">Preimages and postimages</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="features/cdc/cdc-consistency.html">Data Consistency in CDC</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l2"><a class="reference internal" href="features/workload-attributes.html">Workload Attributes</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l1 has-children"><a class="reference internal" href="architecture/index.html">ScyllaDB Architecture</a><input class="toctree-checkbox" id="toctree-checkbox-19" name="toctree-checkbox-19" type="checkbox"/><label for="toctree-checkbox-19"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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||
<li class="toctree-l2"><a class="reference internal" href="architecture/tablets.html">Data Distribution with Tablets</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="architecture/ringarchitecture/index.html">ScyllaDB Ring Architecture</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="architecture/architecture-fault-tolerance.html">ScyllaDB Fault Tolerance</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="architecture/console-CL-full-demo.html">Consistency Level Console Demo</a></li>
|
||
<li class="toctree-l2 has-children"><a class="reference internal" href="architecture/anti-entropy/index.html">ScyllaDB Anti-Entropy</a><input class="toctree-checkbox" id="toctree-checkbox-20" name="toctree-checkbox-20" type="checkbox"/><label for="toctree-checkbox-20"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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||
<li class="toctree-l3"><a class="reference internal" href="architecture/anti-entropy/hinted-handoff.html">ScyllaDB Hinted Handoff</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="architecture/anti-entropy/read-repair.html">ScyllaDB Read Repair</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="operating-scylla/procedures/maintenance/repair.html">ScyllaDB Repair</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l2 has-children"><a class="reference internal" href="architecture/sstable/index.html">SSTable</a><input class="toctree-checkbox" id="toctree-checkbox-21" name="toctree-checkbox-21" type="checkbox"/><label for="toctree-checkbox-21"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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||
<li class="toctree-l3"><a class="reference internal" href="architecture/sstable/sstable2/index.html">ScyllaDB SSTable - 2.x</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="architecture/sstable/sstable3/index.html">ScyllaDB SSTable - 3.x</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l2"><a class="reference internal" href="architecture/compaction/compaction-strategies.html">Compaction Strategies</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="architecture/raft.html">Raft Consensus Algorithm in ScyllaDB</a></li>
|
||
<li class="toctree-l2"><a class="reference internal" href="architecture/zero-token-nodes.html">Zero-token Nodes</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l1 has-children"><a class="reference internal" href="troubleshooting/index.html">Troubleshooting ScyllaDB</a><input class="toctree-checkbox" id="toctree-checkbox-22" name="toctree-checkbox-22" type="checkbox"/><label for="toctree-checkbox-22"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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<li class="toctree-l2 has-children"><a class="reference internal" href="troubleshooting/support/index.html">Errors and Support</a><input class="toctree-checkbox" id="toctree-checkbox-23" name="toctree-checkbox-23" type="checkbox"/><label for="toctree-checkbox-23"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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||
<li class="toctree-l3"><a class="reference internal" href="troubleshooting/report-scylla-problem.html">Report a ScyllaDB problem</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="troubleshooting/error-messages/index.html">Error Messages</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="troubleshooting/log-level.html">Change Log Level</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l2 has-children"><a class="reference internal" href="troubleshooting/startup/index.html">ScyllaDB Startup</a><input class="toctree-checkbox" id="toctree-checkbox-24" name="toctree-checkbox-24" type="checkbox"/><label for="toctree-checkbox-24"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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||
<li class="toctree-l3"><a class="reference internal" href="troubleshooting/change-ownership.html">Ownership Problems</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="troubleshooting/scylla-wont-start.html">ScyllaDB will not Start</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="troubleshooting/python-error-no-module-named-yaml.html">ScyllaDB Python Script broken</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l2 has-children"><a class="reference internal" href="troubleshooting/upgrade/index.html">Upgrade</a><input class="toctree-checkbox" id="toctree-checkbox-25" name="toctree-checkbox-25" type="checkbox"/><label for="toctree-checkbox-25"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
|
||
<li class="toctree-l3"><a class="reference internal" href="troubleshooting/missing-dotmount-files.html">Inaccessible configuration files after ScyllaDB upgrade</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l2 has-children"><a class="reference internal" href="troubleshooting/cluster/index.html">Cluster and Node</a><input class="toctree-checkbox" id="toctree-checkbox-26" name="toctree-checkbox-26" type="checkbox"/><label for="toctree-checkbox-26"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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||
<li class="toctree-l3"><a class="reference internal" href="troubleshooting/handling-node-failures.html">Handling Node Failures</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="troubleshooting/failed-add-remove-replace.html">Failure to Add, Remove, or Replace a Node</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="troubleshooting/failed-decommission.html">Failed Decommission Problem</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="troubleshooting/timeouts.html">Cluster Timeouts</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="troubleshooting/node-joined-without-any-data.html">Node Joined With No Data</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="troubleshooting/nodetool-nullpointerexception.html">NullPointerException</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="troubleshooting/failed-schema-sync.html">Failed Schema Sync</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l2 has-children"><a class="reference internal" href="troubleshooting/modeling/index.html">Data Modeling</a><input class="toctree-checkbox" id="toctree-checkbox-27" name="toctree-checkbox-27" type="checkbox"/><label for="toctree-checkbox-27"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
|
||
<li class="toctree-l3"><a class="reference internal" href="troubleshooting/large-partition-table.html">ScyllaDB Large Partitions Table</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="troubleshooting/large-rows-large-cells-tables.html">ScyllaDB Large Rows and Cells Table</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="troubleshooting/debugging-large-partition.html">Large Partitions Hunting</a></li>
|
||
<li class="toctree-l3"><a class="reference internal" href="troubleshooting/failed-update-schema.html">Failure to Update the Schema</a></li>
|
||
</ul>
|
||
</li>
|
||
<li class="toctree-l2 has-children"><a class="reference internal" href="troubleshooting/storage/index.html">Data Storage and SSTables</a><input class="toctree-checkbox" id="toctree-checkbox-28" name="toctree-checkbox-28" type="checkbox"/><label for="toctree-checkbox-28"><i class="icon-chevron-right"></i></label><div class="break"></div><ul>
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||
<li class="toctree-l3"><a class="reference internal" href="troubleshooting/space-up.html">Space Utilization Increasing</a></li>
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