Adding new ESXi hosts to a cluster that already has VirtuCache.

Here are the prerequisites and steps to add new ESXi hosts to an existing cluster that has VirtuCache installed.

Prerequisites.

Before you add new ESXi hosts to an ESXi cluster that already has VirtuCache installed on other hosts, make sure that you have the below three things in place.

1. That you have a temporary or a permanent VirtuCache license key for the new ESXi hosts;
2. That you have the same VirtuCache caching driver software (.vib file) that you had installed on the other hosts in the cluster earlier. This ensures that you install the same version of VirtuCache caching driver software on the new ESXi hosts, that you have on the hosts you had installed VirtuCache on earlier. It is a requirement that you have the same VirtuCache build number installed on all hosts in the cluster. Here is a KB article on how to find out the specific build number that you have on the other hosts in the cluster and the specific build number of the .vib file; and
3. Ideally, you have the same cache media type and cache capacity in this new host that you have on the other hosts.

If you don’t have #1 and #2 above, Virtunet will be happy to send you a temporary license file for the new hosts and the same caching driver software build that you have installed on the other hosts in the cluster.

Steps to add new hosts to an existing ESXi cluster that has VirtuCache installed.

Make sure that the new host that you have just added to the ESXi cluster is in maintenance mode. Once the host is added to the cluster and is still in maintenance mode, install VirtuCache driver software and license file on that host. Configure the cache device and replication network and make sure that caching is on.

Repeat this process for each new host that you add to the ESXi cluster.

Care needs to be taken to ensure that:
1. There is no chance of vmotion between hosts that have VirtuCache installed and those hosts that don’t, while the hosts are being added to the cluster and/or while VirtuCache is being installed on these new hosts. Hence the requirement for Maintenance mode during this process.
2. That all hosts in the cluster have the same VirtuCache driver build installed. This is for reasons listed on this KB article.
3. And that the replication network is configured on the new hosts in the same way as on the older hosts, else VirtuCache read re-directs and write replication will not work.