Zimbra OSS - Red Hat Cluster Suite

[danny.sierra@omtech.net]

Hi guys, has anyone has tried to install zimbra oss 5.0.18 with red hat cluster suite? i tried with drbd and works ok but i'm having trouble with Red Hat cluster, i know that network edition works fine but how can do for oss?

[Himanshu]

Danny,

How is the drbd performing and what improvement u r lookig fr with cluster suite ?

[danny.sierra@omtech.net]

Well drbd is a fine way to configure a cluster but you got a big risk to lose your data because you are having all your data in a virtual partition wich is replicated between two machines, if the filesystem in one of the boxes fail, you got no more cluster so you still got one point of failure.


Well with Red Hat Cluster Suite, you install all files on a SAN and also you use gfs wich allows to do many writing at the same time if both boxes or one of the explodes or filesystem fails you still got your data somewere that's what i want to achieve.

Also drbd and hertbeat looks every time if the ping signal is over, rhcs also checks fences devices such as warnings on blades or something like it and also services to check if the server is ok

[Klug]

RHCS won't bring much more...

The scripts will check ZCS is running on the "primary" node. If there's a problem with ZCS (script finds one of the services if down), it will migrate to the "secondary" node.

It won't rebuild the partition nor data (might be needed if ZCS went down badly) and if there's a data issue, ZCS won't start either on "secondary" node so you'll get :
. "primary" node down because of fencing
. broken data
. "secondary" node up but ZCS unable to start on it
. broken cluster

Today, I'd rather have a good monitoring solution and manual failover than RHCS.
Or go the "VM" way (if primary host goes down, VM is moved to secondary node), because this way we're handling only hardware failures.

IMHO, the issue in RHCS is the way it triggers the move to secondary node.
If there's an hardware issue, it's OK.
If it's a software issue, automatic failover is not always good.

Oh, and BTW, don't use GFS with RHCS and ZCS.