Databases on m5:
labsdbaccounts mailman3 mailman3web striker test_labsdbaccounts toolhub cxserverdb
When: Thursday 1st Sept - 14:00 UTC
Impact: Writes will be disabled for around 1 minute.
Failover process
OLD MASTER: db1107
NEW MASTER: db1183
- Check configuration differences between new and old master
$ pt-config-diff h=db1107.eqiad.wmnet,F=/root/.my.cnf h=db1183.eqiad.wmnet,F=/root/.my.cnf
- Silence alerts on all hosts
- Topology changes: move everything under db1183
db-switchover --timeout=25 --only-slave-move db1107.eqiad.wmnet db1183.eqiad.wmnet
- Disable puppet db1107 and db1183 puppet agent --disable "switchover to db1183"
- Merge gerrit: https://gerrit.wikimedia.org/r/c/operations/puppet/+/828903
- Run puppet on dbproxy1017 and dbproxy1021 and check the config
puppet agent -tv && cat /etc/haproxy/conf.d/db-master.cfg
- Start the failover: !log Failover m5 from db1107 to db1183 - T316744
- DB switchover
root@cumin1001:~/wmfmariadbpy/wmfmariadbpy# db-switchover --read-only-master --skip-slave-move db1107 db1183
- Reload haproxies (dbproxy1021 is the active one)
dbproxy1017: systemctl reload haproxy && echo "show stat" | socat /run/haproxy/haproxy.sock stdio dbproxy1021: systemctl reload haproxy && echo "show stat" | socat /run/haproxy/haproxy.sock stdio
- kill connections on the old master (db1107)
pt-kill --print --kill --victims all --match-all F=/dev/null,S=/run/mysqld/mysqld.sock
- Restart puppet on old and new masters (for heartbeat):db1107 and db1183 puppet agent --enable && puppet agent -tv
- Check affected services
- Clean orchestrator heartbeat to remove the old masters' one, otherwise Orchestrator will show lag: delete from heartbeat where server_id=171966678;
- Close this ticket and create a ticket to move db1107 to s1: T316870