I think every question you asked screams NFS but I understand the license is expensive. Your hosts are your ESX hosts so 64 should not be an issue unless you're talking about a massive set up (and I don't think VMware supports that large currently, at least not in a single cluster). It should be referring to hosts, not VMs... unless you're using NPIV in which case I have no idea.

Back to question 1, I've never seen a good answer on this. I think it is always going to depend on your environment but in my experience the bottleneck for literally 95%+ VMware implementations has been at the spindle level not how you've configured your LUNs. I've got a 3070 so probably a bit slower than what you are working with running 400 VMs from tiny to massive (32 gig SQL 2008 data warehouse) via NFS, several FC connected pSeries boxes that I can't get rid of as well as home/dept directories for around 1k users.

Still spindle bound :-)

________________________________

From: owner-toasters@mathworks.com [mailto:owner-toasters@mathworks.com] On Behalf Of Fred Grieco Sent: Tuesday, April 20, 2010 12:49 PM To: toasters@mathworks.com Cc: fred.grieco@dds.net; paul.regan@dds.co.uk Subject: FC port fan-in

Toasters,

I am looking at the specs for the Netapp 3140 cluster, and attempting to find the answers to two questions:

1) How many VMWare hosts can I have looking at the same set of LUNs? Before I have real-world performance issues?

2) How many multipathed hosts can I have, total, pointed at a four-fc-port cluster?

The limit in #1, according to NOW, is 256 (256 initiators per igroup). What are your experiences in with this in large VMWare farms?

#2 seems to be 256 according to NOW, but there is a limit called "FC port fan-in" of 64. This would seem to limit the total number of HBA initiators pointing at a port to 64, which, since all my HBAs see all my ports, would limit the total hosts to ... 64? What does this number mean effectively for hosts with two cards?

TIA, Fred

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