The following steps are performed in sequence as part of the
Raft-based recovery procedure:
- set `recovery_leader` to the host ID of the recovery leader in
`scylla.yaml` on all live nodes,
- send the `SIGHUP` signal to all Scylla processes to reload the config,
- perform a rolling restart (with the recovery leader being restarted
first).
These steps are not intuitive and more complicated than they could be.
In this PR, we simplify these steps. From now on, we will be able to
simply set `recovery_leader` on each node just before restarting it.
Apart from making necessary changes in the code, we also update all
tests of the Raft-based recovery procedure and the user-facing
documentation.
Fixesscylladb/scylladb#25015
The Raft-based procedure was added in 2025.2. This PR makes the
procedure simpler and less error-prone, so it should be backported
to 2025.2 and 2025.3.
Closesscylladb/scylladb#25032
* github.com:scylladb/scylladb:
docs: document the option to set recovery_leader later
test: delay setting recovery_leader in the recovery procedure tests
gossip: add recovery_leader to gossip_digest_syn
db: system_keyspace: peers_table_read_fixup: remove rows with null host_id
db/config, gms/gossiper: change recovery_leader to UUID
db/config, utils: allow using UUID as a config option
ec7832cc84