NetApp Initiator Group Best Practices for VMFS LUNs

I’m often asked by my clients the best way to configure NetApp igroups when connecting to VMware VMFS LUNs, especially after I deploy a new system for them and I’m training them on their use.  I appreciate the question because it means someone’s actually thinking through why something is configured the way it is rather than just throwing something together.

The Problem

So this is what I see a lot of out in the field.  Single igroups are created with multiple initiators from multiple hosts.  This can be a problem, though, as I’ll show you.  Functionally, this configuration will work – each host will be able to see each LUN, all things being equal.  The problem arises when you want to either 1. remove a host from the igroup or 2. stop presenting a LUN to only a subset of hosts.
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