[Linux-cluster] fence device

[Steven Dake]

On Mon, 2009-08-17 at 01:14 +0200, Jerome Fenal wrote:
> Le mercredi 12 août 2009 à 09:08 +0200, LEROUX Ludovic a écrit :
> > i have a linux redhat cluster with two redhat 5.3 nodes.
> > I have a shared iscsi disk with gfs.
> > And i created an oracle service which mounts the gfs file system and
> > start an oracle instance in fail over mode.
> > I have two questions:
> > 1°) I don't have a fence device. Is it possible to create a cluster
> > without a fence device? 
> 
> Having a fencing device is mandatory for supportability.
> You can open a support ticket to get directions in order to correct this
> with your actual setup.
> 
> > 2°) is it possible to create a high available cluster with two or more
> > nodes which works together (for example http server).
> 
> You mean multiple processes across multiple nodes for one service ?
> No.
> 
It is possible using the cpg C programming interface but requires custom
development of the server application.  If you are developing your own
server application, you may find this method of HA (replicated state)
very useful.

man evs_overview to see the programming model.  man -k cpg will show a
list of the apis.

Looks like we need a cpg_overview man page.

regards
-steve

> Regards,
> 
> J.
>