Hello,
I am using Pacemaker 1.1.12 together with Corosync 2.4.3 in my cluster
environment. I have two nodes in cluster that are in different LAN
locations. It may be situation that nodes will not be able to connect with
each other because of network failure. In that situation split brain can
occur if we add new configuration on both nodes but that configuration will
be different on each node.
1. After repairing network failure, both nodes will rejoin to cluster, but
there are two different configurations. Which cib configuration will be
used ? Is it possible that configuration on first node will be overwriten
by second node ?
2. Is there any possibility to use multiple live cib configurations to
prevent from losing configuration in split brain situation ?
My split brain example:
1. Both nodes are up and cib configuration is synced
2. node1 has vip1 as resource, node2 has vip2 as resource
3. network failure, nodes cannot sync configuration
4. admin add vip2 on node1
5. second admin add vip3 on node2 (now we have split brain in configuration)
6. network failure resolved, nodes are rejoining the cluster
7. cib configuration is synced and probably we lost configuration from
node1 or node2
How to solve this problem ?
Thank you in advance !
Best Regards.
Adam Blaszczykowski
I am using Pacemaker 1.1.12 together with Corosync 2.4.3 in my cluster
environment. I have two nodes in cluster that are in different LAN
locations. It may be situation that nodes will not be able to connect with
each other because of network failure. In that situation split brain can
occur if we add new configuration on both nodes but that configuration will
be different on each node.
1. After repairing network failure, both nodes will rejoin to cluster, but
there are two different configurations. Which cib configuration will be
used ? Is it possible that configuration on first node will be overwriten
by second node ?
2. Is there any possibility to use multiple live cib configurations to
prevent from losing configuration in split brain situation ?
My split brain example:
1. Both nodes are up and cib configuration is synced
2. node1 has vip1 as resource, node2 has vip2 as resource
3. network failure, nodes cannot sync configuration
4. admin add vip2 on node1
5. second admin add vip3 on node2 (now we have split brain in configuration)
6. network failure resolved, nodes are rejoining the cluster
7. cib configuration is synced and probably we lost configuration from
node1 or node2
How to solve this problem ?
Thank you in advance !
Best Regards.
Adam Blaszczykowski