couple minor formatting fixes.
Closesscylladb/scylladb#17518
* github.com:scylladb/scylladb:
docs: remove leading space in table element
docs: remove space in words
Introduces collapsible dropdowns for images reference docs. With this update, only the latest version's details will be displayed open by default. Information about previous versions will be hidden under dropdowns, which users can expand as needed. This enhancement aims to make pages shorter and easier to navigate.
Closesscylladb/scylladb#17492
This pull request adds dynamic substitutions for the following variables:
* `.. |CURRENT_VERSION| replace:: {current_version}`
* `.. |UBUNTU_SCYLLADB_LIST| replace:: scylla-{current_version}.list`
* `.. |CENTOS_SCYLLADB_REPO| replace:: scylla-{current_version}.repo`
As a result, it is no longer needed to update the "Installation on Linux" page manually after every new release.
Closesscylladb/scylladb#17544
This commit removes the redundant
"Cluster membership changes and LWT consistency" page.
The page is no longer useful because the Raft algorithm
serializes topology operations, which results in
consistent topology updates.
Closesscylladb/scylladb#17523
This PR updates the procedures that changed as a result of introducing Raft-based topology.
Refs https://github.com/scylladb/scylladb/issues/15934
Applied the updates from https://docs.google.com/document/d/1BgZaYtKHs2GZKAxudBZv4G7uwaXcRt2jM6TK9dctRQg/edit
In addition, it adds a placeholder for the 5.4-to-6.0 upgrade guide, as a file included in that guide, Enable Raft topology, is referenced from other places in the docs.
Closesscylladb/scylladb#17500
* github.com:scylladb/scylladb:
doc: replace "Raft Topology" with "Consistent Topology"
doc: (Raft topology) update Removenode
doc: (Raft topology) update Upscale a Cluster
doc:(Raft topology)update Membership Change Failures
doc: doc: (Raft topology) update Replace Dead Node
doc: (Raft topology) update Remove a Node
doc: (Raft topology) update Add a New DC
doc: (Raft topology) update Add a New Node
doc: (Raft topology) update Create Cluster (EC2)
doc: (Raft topology) update Create Cluster (n-DC)
doc: (Raft topology) update Create Cluster (1DC)
doc: include the quorum requirement file
doc: add the quorum requirement file
doc: add placeholder for Enable Raft topology page
this "misspelling" was identified by codespell. actually, it's not
quite a misspelling, as "UPDATE" and "INSERT" are keywords in CQL.
so we intended to emaphasis them, so to make codespell more useful,
and to preserve the intention, let's quote the keywords with backticks.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#17391
This commit updates the Nodetool Removenode page
with reference to the Raft-related topology.
Specifically, it removes outdated warnings, and
adds the information about banning removed and ignored
nodes from the cluster.
This commit updates the Handling Cluster Membership Change Failures page
with reference to the Raft-related topology.
Specifically, it adds a note that the page only applies when
Raft-based topology is not enabled.
In addition, it removes the Raft-enabled option.
This commit updates the Replace a Dead Node page
with reference to the Raft-related topology.
Specifically, it removes the previous pre-Raft limitation
to replace the nodes one by one and the requirement to ensure
that the the replaced node will never come back to the cluster
In addition, a warning is added to indicate the limitations
when Raft-base topology is not enabled upon upgrade from 5.4.
This commit updates the Remove a Node page
with reference to the Raft-related topology.
Specifically, it removes the previous pre-Raft limitation
to remove the nodes one by one and the requirement to ensure
that the the removed node will never come back to the cluster
In addition, a warning is added to indicate the limitations
when Raft-base topology is not enabled upon upgrade from 5.4.
This commit updates the Add a New DC) page
with reference to the Raft-related topology.
Specifically, it removes the previous pre-Raft limitation
to bootstrap the nodes one by one.
In addition, a warning is added to indicate the limitations
when Raft-base topology is not enabled upon upgrade from 5.4.
This commit updates the Add a New Node (Out Scale) page
with reference to the Raft-related topology.
Specifically, it removes the previous pre-Raft limitation
to bootstrap the nodes one by one.
In addition, a warning is added to indicate the limitations
when Raft-base topology is not enabled upon upgrade from 5.4.
This commit updates the Create Cluster (EC2) page
with reference to the Raft-related topology.
Specifically, it removes the previous pre-Raft limitation
to bootstrap the nodes one by one.
In addition, it updates the concept of the seed node.
This commit updates the Create Cluster (Multi DC) page
with reference to the Raft-related topology.
Specifically, it removes the previous pre-Raft limitation
to bootstrap the nodes one by one.
In addition, it updates the concept of the seed node.
This commit updates the Create Cluster (Single DC) page
with reference to the Raft-related topology.
Specifically, it removes the previous pre-Raft limitation
to bootstrap the nodes one by one.
In addition, it updates the concept of the seed node.
otherwise sphinx would consider "Within which Data Center the"
as the "term" part of an entry in a definition list, and
"node is located" as the definition part of this entry.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
* remove space in "Exceptions", otherwise it renders like "Except"
"tions", which does not look right.
* remove space in "applicable".
* remove space in "Transport".
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
This commit adds a placeholder for the Enable Raft-based Topology page
in the 5.4-to-6.0 upgrade guide.
This page needs to be referenced from other pages in the docs.
When we create a CDC generation and ring-delay is non-zero, the
timestamp of the new generation is in the future. Hence, we can
have multiple generations that can be written to. However, if we
add a new node to the cluster with the Raft-based topology, it
receives only the last committed generation. So, this node will
be rejecting writes considered correct by the other nodes until
the last committed generation starts operating.
In scylladb/scylladb#17134, we have allowed sending writes to the
previous CDC generations. So, the situation became even more
complicated. This PR adjusts the Raft-based topology
to ensure all required generations are loaded into memory and their
data isn't cleared too early.
To load all required generations into memory, we replace
`current_cdc_generation_{uuid, timestamp}` with the set containing
IDs of all committed generations - `committed_cdc_generations`.
To ensure this set doesn't grow endlessly, we remove an entry from
this set together with the data in CDC_GENERATIONS_V3.
Currently, we may clear a CDC generation's data from
CDC_GENERATIONS_V3 if it is not the last committed generation
and it is at least 24 hours old (according to the topology
coordinator's clock). However, after allowing writes to the
previous CDC generations, this condition became incorrect. We
might clear data of a generation that could still be written to.
The new solution introduced in this PR is to clear data of the
generations that finished operating more than 24 hours ago.
Apart from the changes mentioned above, this PR hardens
`test_cdc_generation_clearing.py`.
Fixesscylladb/scylladb#16916Fixesscylladb/scylladb#17184Fixesscylladb/scylladb#17288Closesscylladb/scylladb#17374
* github.com:scylladb/scylladb:
test: harden test_cdc_generation_clearing
test: test clean-up of committed_cdc_generations
raft topology: clean committed_cdc_generations
raft topology: clean only obsolete CDC generations' data
storage_service: topology_state_load: load all committed CDC generations
system_keyspace: load_topology_state: fix indentation
raft topology: store committed CDC generations' IDs in the topology
This PR removes information about outdated versions, including disclaimers and information when a given feature was added.
Now that the documentation is versioned, information about outdated versions is unnecessary (and makes the docs harder to read).
Fixes https://github.com/scylladb/scylladb/issues/12110Closesscylladb/scylladb#17430
Set filesystem permissions for the maintenance socket to 660 (previously it was 755) to allow a scyllaadm's group to connect.
Split the logic of creating sockets into two separate functions, one for each case: when it is a regular cql controller or used by maintenance_socket.
Fixes https://github.com/scylladb/scylladb/issues/16487.
Closesscylladb/scylladb#17113
* github.com:scylladb/scylladb:
maintenance_socket: add option to set owning group
transport/controller: get rid of magic number for socket path's maximal length
transport/controller: set unix_domain_socket_permissions for maintenance_socket
transport/controller: pass unix_domain_socket_permissions to generic_server::listen
transport/controller: split configuring sockets into separate functions
When we create a CDC generation and ring-delay is non-zero, the
timestamp of the new generation is in the future. Hence, we can
have multiple generations that can be written to. However, if we
add a new node to the cluster with the Raft-based topology, it
receives only the last committed generation. So, this node will
be rejecting writes considered correct by the other nodes until
the last committed generation starts operating.
In scylladb/scylladb#17134, we have allowed sending writes to the
previous CDC generations. So, the situation became even more
complicated. We need to adjust the Raft-based topology to ensure
all required generations are loaded into memory and their data
isn't cleared too early.
This patch is the first step of the adjustment. We replace
`current_cdc_generation_{uuid, timestamp}` with the set containing
IDs of all committed generations - `committed_cdc_generations`.
This set is sorted by timestamps, just like
`unpublished_cdc_generations`.
This patch is mostly refactoring. The last generation in
`committed_cdc_generations` is the equivalent of the previous
`current_cdc_generation_{uuid, timestamp}`. The other generations
are irrelevant for now. They will be used in the following patches.
After introducing `committed_cdc_generations`, a newly committed
generation is also unpublished (it was current and unpublished
before the patch). We introduce `add_new_committed_cdc_generation`,
which updates both sets of generations so that we don't have to
call `add_committed_cdc_generation` and
`add_unpublished_cdc_generation` together. It's easy to forget
that both of them are necessary. Before this patch, there was
no call to `add_unpublished_cdc_generation` in
`topology_coordinator::build_coordinator_state`. It was a bug
reported in scylladb/scylladb#17288. This patch fixes it.
This patch also removes "the current generation" notion from the
Raft-based topology. For the Raft-based topology, the current
generation was the last committed generation. However, for the
`cdc::metadata`, it was the generation operating now. These two
generations could be different, which was confusing. For the
`cdc::metadata`, the current generation is relevant as it is
handled differently, but for the Raft-based topology, it isn't.
Therefore, we change only the Raft-based topology. The generation
called "current" is called "the last committed" from now.
Option `maintenance-socket-group` sets the owning group of the maintenance socket.
If not set, the group will be the same as the user running the scylla node.
With this commit:
- The information about ScyllaDB Enterprise OS support
is removed from the Open Source documentation.
- The information about ScyllaDB Open Source OS support
is moved to the os-support-info file in the _common folder.
- The os-support-info file is included in the os-support page
using the scylladb_include_flag directive.
This update employs the solution we added with
https://github.com/scylladb/scylladb/pull/16753.
It allows to dynamically add content to a page
depending on the opensource/enterprise flag.
Refs https://github.com/scylladb/scylladb/issues/15484Closesscylladb/scylladb#17310
Before this PR, writes to the previous CDC generations would
always be rejected. After this PR, they will be accepted if the
write's timestamp is greater than `now - generation_leeway`.
This change was proposed around 3 years ago. The motivation was
to improve user experience. If a client generates timestamps by
itself and its clock is desynchronized with the clock of the node
the client is connected to, there could be a period during
generation switching when writes fail. We didn't consider this
problem critical because the client could simply retry a failed
write with a higher timestamp. Eventually, it would succeed. This
approach is safe because these failed writes cannot have any side
effects. However, it can be inconvenient. Writing to previous
generations was proposed to improve it.
The idea was rejected 3 years ago. Recently, it turned out that
there is a case when the client cannot retry a write with the
increased timestamp. It happens when a table uses CDC and LWT,
which makes timestamps permanent. Once Paxos commits an entry
with a given timestamp, Scylla will keep trying to apply that entry
until it succeeds, with the same timestamp. Applying the entry
involves writing to the CDC log table. If it fails, we get stuck.
It's a major bug with an unknown perfect solution.
Allowing writes to previous generations for `generation_leeway` is
a probabilistic fix that should solve the problem in practice.
Apart from this change, this PR adds tests for it and updates
the documentation.
This PR is sufficient to enable writes to the previous generations
only in the gossiper-based topology. The Raft-based topology
needs some adjustments in loading and cleaning CDC generations.
These changes won't interfere with the changes introduced in this
PR, so they are left for a follow-up.
Fixesscylladb/scylladb#7251Fixesscylladb/scylladb#15260Closesscylladb/scylladb#17134
* github.com:scylladb/scylladb:
docs: using-scylla: cdc: remove info about failing writes to old generations
docs: dev: cdc: document writing to previous CDC generations
test: add test_writes_to_previous_cdc_generations
cdc: generation: allow increasing generation_leeway through error injection
cdc: metadata: allow sending writes to the previous generations
This commit adds the missing redirections
to the pages whose source files were
previously stored in the install-scylla folder
and were moved to another location.
Closesscylladb/scylladb#17367
This commit updates the Handling Node Failures page
to specify that the quorum requirement refers to both
schema and topology updates.
Closesscylladb/scylladb#17321
This commit removes the Open Source vs. Enterprise matrix
from the Open Source documentation.
In addition, a redirection is added to prevent 404 in the OSS docs,
and to the removed page is replaced with a link to the same page
in the Enterprise docs.
This commit must be reverted enterprise.git, because
we want to keep the Matrix in the Enterprise docs.
Fixes https://github.com/scylladb/scylladb/issues/17289Closesscylladb/scylladb#17295
Instead of adding an asterisk next to "liveness" linking to the glossary, we will temporarily replace them with a hyperlink pending the implementation of tooltip functionality.
Closesscylladb/scylladb#17244
In one of the previous patches, we have allowed writing to the
previous CDC generations for `generation_leeway`. This change has
made the information about failing writes to the previous
generation and the "rejecting writes to an old generation" example
obsolete so we remove them.
After the change, a write can only fail if its timestamp is distant
from the node's timestamp. We add the information about it.
This PR implements a procedure that upgrades existing clusters to use
raft-based topology operations. The procedure does not start
automatically, it must be triggered manually by the administrator after
making sure that no topology operations are currently running.
Upgrade is triggered by sending `POST
/storage_service/raft_topology/upgrade` request. This causes the
topology coordinator to start who drives the rest of the process: it
builds the `system.topology` state based on information observed in
gossip and tells all nodes to switch to raft mode. Then, topology
coordinator runs normally.
Upgrade progress is tracked in a new static column `upgrade_state` in
`system.topology`.
The procedure also serves as an extension to the current recovery
procedure on raft. The current recovery procedure requires restarting
nodes in a special mode which disables raft, perform `nodetool
removenode` on the dead nodes, clean up some state on the nodes and
restart them so that they automatically rebuild the group 0. Raft
topology fits into existing procedure by falling back to legacy topology
operations after disabling raft. After rebuilding the group 0, upgrade
needs to be triggered again.
Because upgrade is manual and it might not be convenient for
administrators to run it right after upgrading the cluster, we allow the
cluster to operate in legacy topology operations mode until upgrade,
which includes allowing new nodes to join. In order to allow it, nodes
now ask the cluster about the mode they should use to join before
proceeding by using a new `JOIN_NODE_QUERY` RPC.
The procedure is explained in more detail in `topology-over-raft.md`.
Fixes: https://github.com/scylladb/scylladb/issues/15008Closesscylladb/scylladb#17077
* github.com:scylladb/scylladb:
test/topology_custom: upgrade/recovery tests for topology on raft
cdc/generation_service: in legacy mode, fall back to raft tables
system_keyspace: add read_cdc_generation_opt
cdc/generation_service: turn off gossip notifications in raft topo mode
cql_test_env: move raft_topology_change_enabled var earlier
group0_state_machine: pull snapshot after raft topology feature enabled
storage_service: disable persistent feature enabler on upgrade
storage_service: replicate raft features to system.peers
storage_service: gossip tokens and cdc generation in raft topology mode
API: add api for triggering and monitoring topology-on-raft upgrade
storage_service: infer which topology operations to use on startup
storage_service: set the topology kind value based on group 0 state
raft_group0: expose link to the upgrade doc in the header
feature_service: fall back to checking legacy features on startup
storage_service: add fiber for tracking the topology upgrade progress
gms: feature_service: add SUPPORTS_CONSISTENT_TOPOLOGY_CHANGES
topology_coordinator: implement core upgrade logic
topology_coordinator: extract top-level error handling logic
storage_service: initialize discovery leader's state earlier
topology_coordinator: allow for custom sharding info in prepare_and_broadcast_cdc_generation_data
topology_coordinator: allow for custom sharding info in prepare_new_cdc_generation_data
topology_coordinator: remove outdated fixme in prepare_new_cdc_generation_data
topology_state_machine: introduce upgrade_state
storage_service: disallow topology ops when upgrade is in progress
raft_group0_client: add in_recovery method
storage_service: introduce join_node_query verb
raft_group0: make discover_group0 public
raft_group0: filter current node's IP in discover_group0
raft_group0: remove my_id arg from discover_group0
storage_service: make _raft_topology_change_enabled more advanced
docs: document raft topology upgrade and recovery
Adds a missing logging import in the file scylladb_common_images extension, which prevents the enterprise build from building.
Additionally, it standardizes logging handling across the extensions and removes "ami" references in Azure and GCP extensions.
Closesscylladb/scylladb#17137
