[Linux-cluster] Howto define two-node cluster in enterpriseenvironment

[Kit Gerrits]

Hello fellow administrator,

If you have a SAN...
Why can't you have the SAN publish the same LUN to the two cluster nodes
simultaneously?
It is only used as a raw device, so there should be no ugly filesystem
side-effects.


Regards,

Kit

-----Original Message-----
From: linux-cluster-bounces at redhat.com
[mailto:linux-cluster-bounces at redhat.com] On Behalf Of Andreas Bleischwitz
Sent: maandag 10 januari 2011 11:25
To: linux-cluster at redhat.com
Subject: [Linux-cluster] Howto define two-node cluster in
enterpriseenvironment

Hello list,

I recently ran into some questions regarding a two-node cluster in an
enterprise environment, where single-point-of-failures were tried to be
eliminated whenever possible.

The situation is the following:
Two-node cluster, SAN-based shared storage - multipathed; host-based
mirrored, bonded NICS, Quorum device as tie-breaker.

Problem:
The quorum device is the single-point-of-failure as the SAN-device could
fail and hence the quorum-disc wouldn't be accessible.
The quorum-disc can't be host-based mirrored, as this would require cmirror
- which depends on a quorate cluster.
One solution: use storage-based mirroring - with extra costs, limited to no
support with mixed storage vendors.
Another solution: Use a third - no service - node which has to have the same
SAN-connections as the other two nodes out of cluster reasons. This node
will idle most of the time and therefore be very uneconomic.

How are such situations usually solved using RHCS? There must be a way of
configuring a two-nodecluster without having a SPOF defined.

HP had a quorum-host with their no longer maintained Service Guard, which
could do quorum for more than on cluster at once.

Any suggestions appreciated.

Best regrads,

Andreas Bleischwitz

--
Linux-cluster mailing list
Linux-cluster at redhat.com
https://www.redhat.com/mailman/listinfo/linux-cluster