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
The parameter was needed when nodes were addressed by IP, so during
replace with the same IP a new node had to "hide" itself from the
cluster to not get accidentally confused with the old node. Now,
when nodes are addressed by host id the situation is impossible.
The function checks if a node with provided id is alive. If it fails to map id to ip
or there is no state for the ip found the node is considered to be dead.