Comments on: Galera replication – how to recover a PXC cluster

By: Jaz

Jaz — Mon, 03 Dec 2018 14:14:22 +0000

service mysql start –wsrep_sst_donor=nodeC

This command is not working on CentOS 7

By: Przemysław Malkowski

Przemysław Malkowski — Thu, 17 Dec 2015 00:00:48 +0000

Blog comments section is not suitable for certain cases trouble shooting. I’d suggest using our forums: https://www.percona.com/forums/questions-discussions/percona-xtradb-cluster

By: Sibin John

Sibin John — Mon, 30 Nov 2015 13:19:50 +0000

Hi ,
I configured 3 node percona cluster for cloudstack deployment and as per the above description the cluster will have to start automatically even if there is a power failure occur . But in my case after a down or failure of all the three nodes ,the cluster is not coming up .While booting the machine it is trying to make the cluster but failing ..showing as cluster failed to start , how can I resolve it . It creates a lot of problems for my environment ,since it is going make accessible by public . Expecting your quick and relevant solution …

Thanks and regards,
SIbin John

By: George

George — Fri, 13 Feb 2015 17:09:33 +0000

Hi,

thanks for your instructions on all these cases. I had a failure in two percona cluster nodes (crashed after power failure), and i managed to start only one of them using /etc/init.d/mysql start –wsrep_cluster_address=gcomm://

The other one cannot start saying
Starting MySQL (Percona XtraDB Cluster).The server quit wit[FAILED]ating PID file (/percona/var/lib/mysql/san1.uk.arithon.com.pid).
MySQL (Percona XtraDB Cluster) server startup failed!

Is there anything else i can try ?

thanks,

George

By: Przemysław Malkowski

Przemysław Malkowski — Fri, 30 Jan 2015 08:13:48 +0000

Paweł, Galera has a special ability to use alternative path for communication called message relaying. In this case, as both A and B can communicate with C, they will use C as a relay node and the cluster should continue functioning.

By: Paweł

Paweł — Mon, 12 Jan 2015 21:30:49 +0000

What would happen to cluster if network was down between A-B, but A-C and B-C was fully functioning?

By: Nick

Nick — Wed, 19 Nov 2014 22:48:18 +0000

Thank you for this easy to follow and comprehensive post. Demystification goes such a long way towards making clustering more approachable. Just imagine what we’ll need to demystify once clustering becomes the norm.

By: Aray

Aray — Fri, 14 Nov 2014 16:08:48 +0000

Hi,

I have a 3 node PXC. Yesterday, one node of it crashed. Now it was running on two nodes. I tried to recover the crashed node but nothing helped so I decided to build it from scratch. I emptied the mysql data directory and started mysql on this crashed node. Doing this made the other two nodes in cluster unreachable and were shown as down. clustercheck was showing 503 n these servers. I stopped mysql on these two nodes but now I can only bootstrap one node and rest two are down. I know this is all messed up. Can I build the other two nodes by copying data from thrid running(bootstrapped) node? and will other two nodes start fine after data is copied?

Appreciate your help please.

Thanks,
Aray

By: Przemysław Malkowski

Przemysław Malkowski — Mon, 15 Sep 2014 16:00:57 +0000

Martin,
I just checked with MariaDB Cluster 10.0.13 (latest available via MariaDB apt repository) and the pc.recovery option is not present:
root@node1:~# mysql -e “show variables like ‘wsrep_provider_options’\G”|sed ‘s/; /\n/g’|grep ‘pc.’
pc.announce_timeout = PT3S
pc.checksum = false
pc.ignore_quorum = false
pc.ignore_sb = false
pc.linger = PT20S
pc.npvo = false
pc.version = 0
pc.wait_prim = true
pc.wait_prim_timeout = P30S
pc.weight = 1

By: Martin

Martin — Thu, 11 Sep 2014 12:01:35 +0000

Is it possbile to enable automatic recovery on MariaDB Galera Cluster 10.0.13 when all nodes go down without proper shutdown procedure (Scenario 6)?