If an entire node happens to get killed, and that node currently does not hold the Galera IP (192.168.122.99 in our example), then the other nodes simply continue to function normally, and you can connect to and use them without interruption. In the example below, alice has left the cluster:

============
Last updated: Mon Dec  3 22:24:55 2012
Last change: Mon Dec  3 22:23:19 2012 via crmd on charlie
Stack: openais
Current DC: charlie - partition with quorum
Version: 1.1.7-ee0730e13d124c3d58f00016c3376a1de5323cff
3 Nodes configured, 3 expected votes
4 Resources configured.
============

Online: [ bob charlie ]
OFFLINE: [ alice ]

Full list of resources:

p_ip_mysql_galera       (ocf::heartbeat:IPaddr2):       Started bob
 Clone Set: cl_mysql [p_mysql]
     Started: [ bob charlie ]
     Stopped: [ p_mysql:0 ]

If the node dies that does currently hold the Galera IP (192.168.122.99 in our example), then the cluster IP shifts to a different node, and when the failed node returns, it can re-fetch the cluster state from the node that took over the IP address. In the example below, in a healthy cluster the IP happens to be running on bob:

============
Last updated: Mon Dec  3 22:32:35 2012
Last change: Mon Dec  3 22:23:19 2012 via crmd on charlie
Stack: openais
Current DC: charlie - partition with quorum
Version: 1.1.7-ee0730e13d124c3d58f00016c3376a1de5323cff
3 Nodes configured, 3 expected votes
4 Resources configured.
============

Online: [ bob alice charlie ]

Full list of resources:

p_ip_mysql_galera       (ocf::heartbeat:IPaddr2):       Started bob
 Clone Set: cl_mysql [p_mysql]
     Started: [ alice bob charlie ]

Subsequently, bob is affected by a failure, and the IP address shifts to alice:

============
Last updated: Mon Dec  3 22:33:33 2012
Last change: Mon Dec  3 22:23:19 2012 via crmd on charlie
Stack: openais
Current DC: charlie - partition with quorum
Version: 1.1.7-ee0730e13d124c3d58f00016c3376a1de5323cff
3 Nodes configured, 3 expected votes
4 Resources configured.
============

Online: [ alice charlie ]
OFFLINE: [ bob ]

Full list of resources:

p_ip_mysql_galera       (ocf::heartbeat:IPaddr2):       Started alice
 Clone Set: cl_mysql [p_mysql]
     Started: [ alice charlie ]
     Stopped: [ p_mysql:1 ]

When bob returns, it simply connects to alice (which now hosts the cluster IP), fetches the database state from there, and continues to run:

============
Last updated: Mon Dec  3 22:35:46 2012
Last change: Mon Dec  3 22:23:19 2012 via crmd on charlie
Stack: openais
Current DC: charlie - partition with quorum
Version: 1.1.7-ee0730e13d124c3d58f00016c3376a1de5323cff
3 Nodes configured, 3 expected votes
4 Resources configured.
============

Online: [ bob alice charlie ]

Full list of resources:

p_ip_mysql_galera       (ocf::heartbeat:IPaddr2):       Started alice
 Clone Set: cl_mysql [p_mysql]
     Started: [ alice bob charlie ]

This article originally appeared on the hastexo.com website (now defunct).