The primary aim of this post is to state categorically that VMware supports multiple storage arrays presenting targets and LUNs to a single ESXi host. This statement also includes arrays from multiple vendors. We run with this configuration all the time in our labs, and I know very many of our customers who also have multiple arrays presenting devices to their ESX/ESXi hosts. The issue is that we do not appear to call this out in any of our documentation, although many of our guides and KB articles allude to it.

Some caution must be shown however.

  1. If you have an SATP (Storage Array Type Plugin) that is used by multiple arrays on the same ESXi host, great care must be taken if you decide to change the default PSP (pathing selection policy) for that SATP) as the change will apply to all arrays –
  2. Some storage arrays make recommendations on queue depth and other settings. Note that these are typically global settings, so making a change for one array will impact the queue depth to any other arrays presenting LUNs to that ESXi host –
  3. Another recommendation I would make, and I believe this is in our training materials, is to use single-initiator-single-target zoning when zoning ESXi hosts to FC arrays. This avoids any ‘fabric’ related events occurring on one array from impacting any other array.

With these considerations taken into account, having multiple storage arrays attached to the same ESXi host or hosts is completely supported. I’m going to see if I can get something into our official documentation about this.

Get notification of these blogs postings and more VMware Storage information by following me on Twitter: Twitter @VMwareStorage