Databases on m5:
```
labsdbaccounts
mailman3
mailman3web
striker
test_labsdbaccounts
toolhub
```
When: Thursday 16th at 08:00 UTC
**Impact: Writes will be disabled for around 1 minute.**
Failover process
OLD MASTER: db1106
NEW MASTER: db1176
[] Check configuration differences between new and old master
`$ pt-config-diff h=db1176.eqiad.wmnet,F=/root/.my.cnf h=db1106.eqiad.wmnet,F=/root/.my.cnf `
[] Silence alerts on all hosts: `sudo cookbook sre.hosts.downtime --minutes 60 -r "m5 master switch T332155" 'A:db-section-m5'`
[] Topology changes: move everything under db1176
`db-switchover --timeout=15 --only-slave-move db1106.eqiad.wmnet db1176.eqiad.wmnet`
[] Disable puppet db1176 and db1106
`sudo cumin 'db1176* or db1106*' 'disable-puppet "primary switchover T332155"'`
[] Merge gerrit:
[] Run puppet on dbproxy1017 and dbproxy1021 and check the config
`run-puppet-agent && cat /etc/haproxy/conf.d/db-master.cfg`
[] Start the failover: `!log Failover m5 from db1106 to db1176 - T332155 `
[] DB switchover
`root@cumin1001:~/wmfmariadbpy/wmfmariadbpy# db-switchover --skip-slave-move db1106 db1176`
[] 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 (db1106)
` 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):db1176 and db1106
`sudo cumin 'db1176* or db1106*' 'run-puppet-agent -e "primary switchover T332155"'`
[] Check affected services
[] Clean orchestrator heartbeat to remove the old masters' one, otherwise Orchestrator will show lag: `delete from heartbeat where server_id=171978765;`
[] Create a ticket to move db1106 back to s1: