Happy Day-after Thanksgiving dear readers! I hope everyone is as satisfyingly full on food, friends, and family as I am. As an early gift to myself, I’m writing a PowerShell script that utilizes NetApp’s PowerShell Toolkit. The script will help me quickly determine current volume and LUN settings so I can see what LUNs are at risk of going offline due to out of space conditions. In scripting tradition, I couldn’t find anything online that did exactly what I wanted so I rolled my own!
Here’s what the output looks like. The column names are abbreviated because I expect to have several more columns. The abbreviations are, Volume Thin Provisioning, Fractional Reserve, Snapshots, Volume AutoGrow, Snapshot AutoDelete.
I was recently designing a vSphere Replication and SRM solution for a client and I stated we would use static routes on the ESXi hosts. When asked why, I was able to 1. discuss why the default gateway on the management network wouldn’t work and 2. present some options as to how we could separate the vSphere Replication traffic in a way that would allow flexibility in throttling its bandwidth usage.
You won’t see listed here Network I/O Control because this particular client didn’t have Enterprise Plus licensing and therefore wasn’t using a vDS. In addition, this client was using a fibre channel SAN on top of Cisco UCS with only a single VIC in his blades. This configuration doesn’t work well with NIOC because it doesn’t take into account FC traffic which is sharing bandwidth with all the Ethernet traffic NIOC *is* managing.
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.
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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