HA configuration for KVM machines installed on shared iSCSI storage

My requirement is to provide HA to a Zimbra Server. We want Zimbra files to be installed in a Netapp SAN which is providing around 5.7 TB as a SAN iSCI Drive. Since Netapp comes in with Dual Controller and stable performance, we are unlikely to have any down time.

I have 2 servers each having Xeon processor 6 Core, 32 GB RAM and 2 x 250 GB SSD. These are the two servers where I have installed CentOS 7.6. We would like to have one as primary and the second one as secondary.

Idea is to use the same principle of KVM HA ( What Redhat and even VMware) provides, so that if the primay goes down the IP gets switched to secondary, to create a simple Hot Redudant system.

We have a very few users on Zimbra, but there are a lot of automated emails coming in and we require a very large storage, and hence we are using the Netapp box.

I am able to switch between the KVMs. However I am struggling to figure out how I need to mount the iSCI target, so that the mail application stays alive.

Zimbra typically installs on /opt/. Do I mount the target on /opt/, and if so will it work? Or am I missing something else?

Or should I run the VM of the shared storage itself, and if so how can I configure it.

Zimbra itself is a combination of a database and files, and uses a number of services to keep itself active. Idea of using a shared storage is for Redundancy and high availability.

Appreciate your response and support.

Solution 1:

PACEMAKER and COROSYNC allows HA for Zimbra. Here is a guide - https://github.com/tigerlinux/tigerlinux-extra-recipes/tree/master/recipes/ispapps/zimbra-cluster-centos7 You don't require DRBD since there is a shared SAN storage.