05-02-2013 07:59 AM
We are going to be migrating from our 48000 Directors to our
DCX Directors. We want to make sure we balance and distribute our servers
and storage arrays on the DCX. We understand about distributing the
servers and arrays in the local switching groups on all of the DCX
blades. Does the location of devices in ports make a difference?
For example should servers be located in specific ports and should arrays
be located in specific ports within the local switching group? Based on what I read it does
not matter which port severs and arrays are located in.
05-02-2013 08:07 AM
I'm other opinion.
Blade are designed, some Port are assigned to own ASIC, some other are shared port.
i.e. FC8-48 Port Blade, Port 0-7 are assigne to ASIC 0, port 8-15 are assigned to ASIC 1, remain Port are shared port.
search here in the community, i've posted at several time Blade ASIC Design
05-02-2013 08:17 AM
Thank you. We understand the switching groups and which ports are assigned to which ASIC. We are wondering if servers should be in specific ports and storage on specific ports.
05-02-2013 09:02 AM
----->>> We have FC8-48 blades and I don't recall seeing anything regarding shared ports.
have a fun, and sorry please I've annoying you with my answer.
05-02-2013 09:32 AM
I think you may have misunderstood my reply. I was not doubting you. From what I read that all ports on the local switching group are the same. We really don't understand what the shared area is. If the traffic does not cross the backplane or consume any slot bandwidth within the local switching group then when is the shared area?
05-05-2013 11:36 PM
one asic can talk to another asic only via core blades. even if two mentioned asics are on the same blade.
two ports on the same asic can talk at the full speed together without using backplane and core blades, regardless of their dedicated/shared location.
then what are dedicated and shared? 8g asic has 40 ports. so, on the 48 port blade each of two asics gives you 24 front-end ports and has 16 back-end ports. that's why some front-end ports have their own dedicated back-end ports (and therefore have better access to core blades and to other blades) while other front-end ports have to share back-end ports between them.
i hope somebody will correct me if i'm wrong.
so you'd better allocate dedicated ports: 1) to the ISLs, 2) to the fast shared storage, and then 3) to the very fat/demanding hosts that you might have.
but you don't say what dcx you have and what port blades you have...