[Linux-cluster] redhat cluster in multi SAN

[Jonathan Brassow]

I'm not sure what you mean by multi-SAN.  Do you mean that you have  
two independent storage networks connecting the same machines to the  
same disks, or same machines to different disks, or something else?   
It sounds like you have 1 SAN with two storage devices?  It also  
sounds like your top level services are active/passive, but that your  
storage is setup active/active.  You may consider HA-LVM instead of  
CLVM in this case (http://sourceware.org/cluster/wiki/LVMFailover).

I've seen this scenario where things get frozen...  Turns out that the  
user did not have multipathd running, so multipath was queueing all I/ 
O until a path would come back - effectively freezing everything.

The problem could be a number of things... we may need more  
information if the above doesn't help.

  brassow

On Apr 25, 2008, at 7:41 AM, gnia gnia wrote:

> Hi all,
>
> Situation :  2 nodes cluster (active/active) under RedHat 4.
> Each clusterized service has a multipathed/mirrored LV (one PV on  
> each storage bay -> HP EVA 8000) declared as an FS resource.
> (We decided to implement a multi-SAN environment to prevent from one  
> SAN failure)
> But all clusterized mirrored LVs get frozen and become unusable when  
> we simulate one SAN outage.
>
> According to you experts, what is the best way to implement a  
> storage redundant redhat cluster that wouldn't fail in case of one  
> SAN outage ?
> Is lvm mirroring a godd choice?
>
> Cheers,
> Chris --
> Linux-cluster mailing list
> Linux-cluster at redhat.com
> https://www.redhat.com/mailman/listinfo/linux-cluster