[aklug] OK, akluggers, riddle me this (FC SAN/switching question)

OK, akluggers, here's a question for you.

I have twin SANs in a datacenter. Currently, I have two FC switches,
and connected directly are some servers. Each server has a connection to
each switch.

Each SAN has a single FC connection to each switch, which gives you a
setup that looks like this (in theory - I have only one 'server' in the
diagram here):

http://www.glaven.org/currentFCsetup.pdf

I'm now getting another set of servers and another set of two FC
switches, which will be connected to the SAN.
Each of the new FC switches will have a connection to the SAN, as you
can see in this increasingly confusing diagram:

http://www.glaven.org/newFCsetup.pdf

The question that I have is, "should I connect the two sets of switches
together?"

For example, connect: SW1 to SW3 and SW2 to SW4
Or: Connect SW1 to SW4, and SW2 to SW3

Reasons for: The interconnected switches would give the servers
connected more paths to the SAN, and more throughput. Possible recovery
from a switch failure.
Reasons against: Complicates the setup, requires changing the domain
IDs on the FC switches. I also don't know if this will cause problems
with FC. Also, I doubt I'm using the full capacity of the FC SAN.

I've been "told" that in a two-switch setup, you shouldn't connect the
two switches, even though it provides more paths - although I haven't
been given a concrete reason why.

So, what do you think? I'm using WWPN/WWNN based zoning. I'm just
trying to get as much throughput as I can, without unnecessarily
complicating the setup or causing difficult to determine problems.

-- 
Adam
---------
To unsubscribe, send email to <aklug-request@aklug.org>
with 'unsubscribe' in the message body.