Change Details

When: Thursday 31th - 06:00 AM UTC **Affected wikis:** https://noc.wikimedia.org/conf/highlight.php?file=dblists/s5.dblist NEW primary: db1100 OLD primary: db1130 [x] Check configuration differences between new and old primary: ``` sudo pt-config-diff --defaults-file /root/.my.cnf h=db1130.eqiad.wmnet h=db1100.eqiad.wmnet ``` **Failover prep:** [x] Silence alerts on all hosts: ``` sudo cookbook sre.hosts.downtime --hours 1 -r "Primary switchover s5 T303798" 'A:db-section-s5' ``` [x] Set NEW primary with weight 0 ``` sudo dbctl instance db1100 set-weight 0 sudo dbctl config commit -m "Set db1100 with weight 0 T303798" ``` [] Topology changes, move all replicas under NEW primary ``` sudo db-switchover --timeout=15 --only-slave-move db1130 db1100 ``` [] Disable puppet on both nodes ``` sudo cumin 'db1130* or db1100*' 'disable-puppet "primary switchover T303798"' ``` [] Merge gerrit puppet change to promote NEW primary: https://gerrit.wikimedia.org/r/c/operations/puppet/+/775195 **Failover:** [] Log the failover: ``` !log Starting s5 eqiad failover from db1130 to db1100 - T303798 ``` [] Set section read-only: ``` sudo dbctl --scope eqiad section s5 ro "Maintenance until 05:15 UTC - T303798" sudo dbctl config commit -m "Set s5 eqiad as read-only for maintenance - T303798" ``` [] Check s5 is indeed read-only [] Switch primaries: ``` sudo db-switchover --skip-slave-move db1130 db1100 echo "===== db1130 (OLD)"; sudo db-mysql db1130 -e 'show slave status\G' echo "===== db1100 (NEW)"; sudo db-mysql db1100 -e 'show slave status\G' ``` [] Promote NEW primary in dbctl, and remove read-only ``` sudo dbctl --scope eqiad section s5 set-master db1100 sudo dbctl --scope eqiad section s5 rw sudo dbctl config commit -m "Promote db1100 to s5 primary and set section read-write T303798" ``` [] Restart puppet on both hosts: ``` sudo cumin 'db1130* or db1100*' 'run-puppet-agent -e "primary switchover T303798"' ``` **Clean up tasks:** [] Clean up heartbeat table(s). `delete from heartbeat.heartbeat where server_id=171970593` [] change events for query killer: ``` events_coredb_master.sql on the new primary db1100 events_coredb_slave.sql on the new slave db1130 ``` [] Update DNS: https://gerrit.wikimedia.org/r/c/operations/dns/+/775196 [] Update candidate primary dbctl notes ``` sudo dbctl instance db1130 set-candidate-master --section s5 true sudo dbctl instance db1100 set-candidate-master --section s5 false ``` [] Check zarcillo was updated ** db-switchover should do this. If it fails, do it manually: https://phabricator.wikimedia.org/P13956 [] (If needed): Depool db1130 for maintenance. ``` sudo dbctl instance db1130 depool sudo dbctl config commit -m "Depool db1130 T303798" (dborch1001): sudo orchestrator-client -c untag -i db1100 --tag name=candidate (dborch1001): sudo orchestrator-client -c tag -i db1130 --tag name=candidate ``` [] Apply outstanding schema changes to db1130 (if any) [] Update/resolve this ticket.

When: Thursday 31th - 06:00 AM UTC **Affected wikis:** https://noc.wikimedia.org/conf/highlight.php?file=dblists/s5.dblist NEW primary: db1100 OLD primary: db1130 [x] Check configuration differences between new and old primary: ``` sudo pt-config-diff --defaults-file /root/.my.cnf h=db1130.eqiad.wmnet h=db1100.eqiad.wmnet ``` **Failover prep:** [x] Silence alerts on all hosts: ``` sudo cookbook sre.hosts.downtime --hours 1 -r "Primary switchover s5 T303798" 'A:db-section-s5' ``` [x] Set NEW primary with weight 0 ``` sudo dbctl instance db1100 set-weight 0 sudo dbctl config commit -m "Set db1100 with weight 0 T303798" ``` [x] Topology changes, move all replicas under NEW primary ``` sudo db-switchover --timeout=15 --only-slave-move db1130 db1100 ``` [x] Disable puppet on both nodes ``` sudo cumin 'db1130* or db1100*' 'disable-puppet "primary switchover T303798"' ``` [] Merge gerrit puppet change to promote NEW primary: https://gerrit.wikimedia.org/r/c/operations/puppet/+/775195 **Failover:** [] Log the failover: ``` !log Starting s5 eqiad failover from db1130 to db1100 - T303798 ``` [] Set section read-only: ``` sudo dbctl --scope eqiad section s5 ro "Maintenance until 05:15 UTC - T303798" sudo dbctl config commit -m "Set s5 eqiad as read-only for maintenance - T303798" ``` [] Check s5 is indeed read-only [] Switch primaries: ``` sudo db-switchover --skip-slave-move db1130 db1100 echo "===== db1130 (OLD)"; sudo db-mysql db1130 -e 'show slave status\G' echo "===== db1100 (NEW)"; sudo db-mysql db1100 -e 'show slave status\G' ``` [] Promote NEW primary in dbctl, and remove read-only ``` sudo dbctl --scope eqiad section s5 set-master db1100 sudo dbctl --scope eqiad section s5 rw sudo dbctl config commit -m "Promote db1100 to s5 primary and set section read-write T303798" ``` [] Restart puppet on both hosts: ``` sudo cumin 'db1130* or db1100*' 'run-puppet-agent -e "primary switchover T303798"' ``` **Clean up tasks:** [] Clean up heartbeat table(s). `delete from heartbeat.heartbeat where server_id=171970593` [] change events for query killer: ``` events_coredb_master.sql on the new primary db1100 events_coredb_slave.sql on the new slave db1130 ``` [] Update DNS: https://gerrit.wikimedia.org/r/c/operations/dns/+/775196 [] Update candidate primary dbctl notes ``` sudo dbctl instance db1130 set-candidate-master --section s5 true sudo dbctl instance db1100 set-candidate-master --section s5 false ``` [] Check zarcillo was updated ** db-switchover should do this. If it fails, do it manually: https://phabricator.wikimedia.org/P13956 [] (If needed): Depool db1130 for maintenance. ``` sudo dbctl instance db1130 depool sudo dbctl config commit -m "Depool db1130 T303798" (dborch1001): sudo orchestrator-client -c untag -i db1100 --tag name=candidate (dborch1001): sudo orchestrator-client -c tag -i db1130 --tag name=candidate ``` [] Apply outstanding schema changes to db1130 (if any) [] Update/resolve this ticket.