Recommended 10GE ISCSI SAN switch

Tue May 12 15:05:06 UTC 2015

Paul S. schreef op 12-5-2015 om 15:36:
> Hi guys,
> 
> We're shortly going to be getting some 10G SANs, and I was wondering
> what people were using as SAN switches for 10G SANs.

In one location a HP Procurve 8212zl with 8 SFP+ module, and a 8Gbe
module. Here i'm using a Dell EQL PS6210 SSD cabinet and 24 SATA disk
EQL cabinet on 10G.

In another location on a budget a Netgear M7100 24X with a Dell EQL
PS6010 with Intel S3500 800GB SSDs.

In both locations the switches appear to be doing fine in combination
with VMware ESXi 5.5 and Intel X540-2 cards.

> It is my understanding that low buffer sizes make most 'normal' 10G
> ethernet switches unsuitable for the job.

Not so sure on that, opinions vary a lot here. Similar to the stance on
Flow Control where one vendor will advocate using it and another
advocates against it.

If you only have a single link, then Flow control will sleep the
connection which can impact your performance with a higher Queue depth.
For multiple 1G links the impact is ofcourse a lot less overall.

If you are going to invest in a new SAN make sure to ditch spinning
rust, it's the biggest breakthrough in storage since a while and it's a
factor of a *lot*.

The price doesn't break the bank either, the Dell EQL 6110 was out of
warranty, retail value around $3500 us. The 18 Intel S3500 SSDs were
about 11k euro (16 + 2 spare). In raid 6 that's a good 10TB of storage.
It's a shame that SAN HQ keeps emailing us once a day that the drives
are not original ;)

With that sheer amount of space it's going to take a while before it
ever breaks (wears out). It'll be out of service long before then.

Also, you can max out a single 10G link with about 4-6 recent SSDs, so
smaller cabinets with more uplinks make all the sense. In that respect
the newer cabinets (Dell EQL PS6210) with 24 drives and just 2 10Ge
uplinks are a bit odd. Still, it's nice to do 300-400MB/s in a VM on a 5
year old ESX on a dime. :)

> We're pretty much an exclusive Juniper shop, but are not biased in any
> way -- best tool for the job is what I've been tasked with to find.
> 
> Keeping that in mind, how would something like a EX4550 fare in the
> role? Are there better devices in the same price range?

If the switches work for you and you are comfortable with them I'd count
that as a better argument.

Only budget switches are likely to cause you real grief here.

Kind regards,

Seth