The function checks that the node's state is not left or removed in
gossiper during restart, but with raft topology a removed node will
not be able to contact the cluster to get this information since it will
be banned.
The PR removes most of the code that assumes that group0 and raft topology is not enabled. It also makes sure that joining a cluster in no raft mode or upgrading a node in a cluster that not yet uses raft topology to this version will fail.
Refs #15422
No backport needed since this removes functionality.
Closesscylladb/scylladb#28514
* https://github.com/scylladb/scylladb:
group0: fix indentation after previous patch
raft_group0: simplify get_group0_upgrade_state function since no upgrade can happen any more
raft_group0: move service::group0_upgrade_state to use fmt::formatter instead of iostream
raft_group0: remove unused code from raft_group0
node_ops: remove topology over node ops code
topology: fix indentation after the previous patch
topology: drop topology_change_enabled parameter from raft_group0 code
storage_service: remove unused handle_state_* functions
gossiper: drop wait_for_gossip_to_settle and deprecate correspondent option
storage_service: fix indentation after the last patch
storage_service: remove gossiper bootstrapping code
storage_service: drop get_group_server_if_raft_topolgy_enabled
storage_service: drop is_topology_coordinator_enabled and its uses
storage_service: drop run_with_api_lock_in_gossiper_mode_only
topology: remove code that assumes raft_topology_change_enabled() may return false
test: schema_change_test: make test_schema_digest_does_not_change_with_disabled_features tests run in raft mode
test: schema_change_test: drop schema tests relevant for no raft mode only
topology: remove upgrade to raft topology code
group0: remove upgrade to group0 code
group0: refuse to boot if a cluster is still is not in a raft topology mode
storage_service: refuse to join a cluster in legacy mode
When running unit tests, there's a visible ~1-second sleep
when gossip exits the failure detector loop.
Improve this by adding a condition variable for exiting the loop
and signaling it when any of the exit conditions are satisfied:
the abort_source is pulled, the gossiper is shut down, or the sleep
is complete. We can't just use the abort_source because gossip can be
shut down independently of the rest of the system.
To see the improvement, I ran cql_query_test in dev mode:
Before:
$ time ./build/dev/test/boost/combined_tests -t cql_query_test -- --smp 2 > /dev/null 2>&1
real 2m26.904s
user 0m24.307s
sys 0m13.402s
After:
$ time ./build/dev/test/boost/combined_tests -t cql_query_test -- --smp 2 > /dev/null 2>&1
real 0m26.579s
user 0m24.671s
sys 0m13.636s
Two minutes of real-time saved.
Real-life improvement in test.py will be lower, because of the overhead
of launching pytest for each test case.
Closesscylladb/scylladb#28649
The path removes the code protected by !raft_topology_change_enabled()
since it is no longer reachable. Drop test_lwt_for_tablets_is_not_supported_without_raft
since not raft mode is no longer supported.
There are several places in the code that need to explicitly switch into
gossiper scheduling group. For that they currently call database to
provide the group, but it's better to get gossiper sched group from
gossiper itself, all the more so all those places have gossiper at hand.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Refs #27429
If running with broadcast_address != listen/cql/rpc address, topology
gets confused about the varying addresses. Need to special case
resolve both addresses as "self". I.e. extend broadcast_address
treatment to cql_address as well.
Added export of this via gossiper for symmetry.
And switch to std::source_location.
Upcoming seastar update will deprecate its compatibility layer.
The patch is
for f in $(git grep -l 'seastar::compat::source_location'); do
sed -e 's/seastar::compat::source_location/std::source_location/g' -i $f;
done
and removal of few header includes.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
Closesscylladb/scylladb#27309
In the new Raft-based recovery procedure, live nodes join the new
group 0 one by one during a rolling restart. There is a time window when
some of them are in the old group 0, while others are in the new group
0. This causes a group 0 mismatch in `gossiper::handle_syn_msg`. The
current solution for this problem is to ignore group 0 mismatches if
`recovery_leader` is set on the local node and to ask the administrator
to perform the rolling restart in the following way:
- set `recovery_leader` in `scylla.yaml` on all live nodes,
- send the `SIGHUP` signal to all Scylla processes to reload the config,
- proceed with the rolling restart.
This commit makes `gossiper::handle_syn_msg` ignore group 0 mismatches
when exactly one of the two gossiping nodes has `recovery_leader` set.
We achieve this by adding `recovery_leader` to `gossip_digest_syn`.
This change makes setting `recovery_leader` earlier on all nodes and
reloading the config unnecessary. From now on, the administrator can
simply restart each node with `recovery_leader` set.
However, note that nodes that join group 0 must have `recovery_leader`
set until all nodes join the new group 0. For example, assume that we
are in the middle of the rolling restart and one of the nodes in the new
group 0 crashes. It must be restarted with `recovery_leader` set, or
else it would reject `gossip_digest_syn` messages from nodes in the old
group 0. To avoid problems in such cases, we will continue to recommend
setting `recovery_leader` in `scylla.yaml` instead of passing it as
a command line argument.
We change the type of the `recovery_leader` config parameter and
`gossip_config::recovery_leader` from sstring to UUID. `recovery_leader`
is supposed to store host ID, so UUID is a natural choice.
After changing the type to UUID, if the user provides an incorrect UUID,
parsing `recovery_leader` will fail early, but the start-up will
continue. Outside the recovery procedure, `recovery_leader` will then be
ignored. In the recovery procedure, the start-up will fail on:
```
throw std::runtime_error(
"Cannot start - Raft-based topology has been enabled but persistent group 0 ID is not present. "
"If you are trying to run the Raft-based recovery procedure, you must set recovery_leader.");
```
Since the gossiper works on host ids now it is incorrect to leave this
function to work on ip. It makes it impossible to delete outdated entry
since the "gossiper.get_host_id(endpoint) != id" check will always be
false for such entries (get_host_id() always returns most up -to-date
mapping.
This patch changes gossiper to index nodes by host ids instead of ips.
The main data structure that changes is _endpoint_state_map, but this
results in a lot of changes since everything that uses the map directly
or indirectly has to be changed. The big victim of this outside of the
gossiper itself is topology over gossiper code. It works on IPs and
assumes the gossiper does the same and both need to be changed together.
Changes to other subsystems are much smaller since they already mostly
work on host ids anyway.
This patch ensures that members of the new group 0 can gossip with
members of the old group 0 during rolling restart in the Raft-based
recovery procedure. Without this change, restarted nodes (members of
the new group 0) wouldn't be marked as UP by other nodes (members of
the old group 0), which would decrease availability.
Send digest ack and ack2 by host ids as well now since the id->ip
mapping is available after receiving digest syn. It allows to convert
more code to host id here.
Before calling force_remove_endpoint (which works on ip) the code checks
that the ip maps to the correct id (not not remove a new node that
inherited this ip by mistake). Move the check to the function itself.
It is used by truncate code only and even there it only check if the
returned set is not empty. Check for dead token owners in the truncation
code directly.
The series contains small fixes to the gossiper one of which fixes#21930. Others I noticed while debugged the issue.
Fixes: scylladb/scylladb#21930Closesscylladb/scylladb#21956
* github.com:scylladb/scylladb:
gossiper: do not reset _just_removed_endpoints in non raft mode
gossiper: do not send echo message to yourself
gossiper: do not call apply for the node's old state
