[Pacemaker] Two node cluster and no hardware device for stonith.

Digimer lists at alteeve.ca
Thu Feb 5 08:18:50 UTC 2015


That is the problem that makes geo-clustering very hard to nearly 
impossible. You can look at the Booth option for pacemaker, but that 
requires two (or more) full clusters, plus an arbitrator 3rd location. 
Outside of this though, there really is no way to have geo/stretch 
clustering with automatic failover.

digimer

On 05/02/15 03:38 AM, Dmitry Koterov wrote:
> Could you please give a hint: how to use fencing in case the nodes are
> all in different geo-distributed datacenters? How people do that?
> Because there could be a network disconnection between datacenters, and
> we have no chance to send a stonith signal somewhere.
>
> On Wednesday, February 4, 2015, Andrea <a.bacchi at codices.com
> <mailto:a.bacchi at codices.com>> wrote:
>
>     Digimer <lists at ...> writes:
>
>      >
>      > That fence failed until the network came back makes your fence method
>      > less than ideal. Will it eventually fence with the network still
>     failed?
>      >
>      > Most importantly though; Cluster resources blocked while the
>     fence was
>      > pending? If so, then your cluster is safe, and that is the most
>      > important part.
>      >
>     Hi Digimer
>
>     I'm using for fencing a remote NAS, attached via iscsi target.
>     During network failure, for example on node2, each node try to fence
>     other node.
>     Fencing action on node1 get success, but on node2 fail, because it
>     can't see
>     iscsi target(network is down!) .
>     I thinks it's the reason why node2 doesn't reboot now, because it
>     can't make
>     operation on key reservation and watchdog can't check for this.
>     When network come back, watchdog can check for key registration and
>     reboot
>     node2.
>
>     For clustered filesystem I planned to use ping resource with location
>     constraint as described here
>     http://clusterlabs.org/doc/en-US/Pacemaker/1.0/html/Pacemaker_Explained/ch09s03s03s02.html
>     If the node can't see iscsi target..then..stop AppServer, Filesystem ecc
>
>     But it doesn't works. In the node with network failure i see in the
>     log that
>     pingd is set to 0 but Filesystem resource doesn't stop.
>
>     I will continue testing...
>
>     Thanks
>     Andrea
>
>
>
>
>
>
>     _______________________________________________
>     Pacemaker mailing list: Pacemaker at oss.clusterlabs.org <javascript:;>
>     http://oss.clusterlabs.org/mailman/listinfo/pacemaker
>
>     Project Home: http://www.clusterlabs.org
>     Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
>     Bugs: http://bugs.clusterlabs.org
>
>
>
> _______________________________________________
> Pacemaker mailing list: Pacemaker at oss.clusterlabs.org
> http://oss.clusterlabs.org/mailman/listinfo/pacemaker
>
> Project Home: http://www.clusterlabs.org
> Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf
> Bugs: http://bugs.clusterlabs.org
>


-- 
Digimer
Papers and Projects: https://alteeve.ca/w/
What if the cure for cancer is trapped in the mind of a person without 
access to education?




More information about the Pacemaker mailing list