MDS - Disconnecting ISL

if full zone set distribution enabled, are you using IVR ?

We do have full zoneset distribution enabled, but do not use IVR.

ok, so IVR topology to clean up. I can't think of anything that could be causing issue when you shutdown one of the 9513s.

principle/slave ..does not matter, it will figure it out on its own without any impact. I wanted to double check on full zone set distribution to make sure you have a full copy of zoneset on each switch.

i don't think that would be any impact per say but i like to clean up "relationships" while devices are still online

for example here is sample IVR topology

# show ivr vsan-topology 


AFID  SWITCH WWN                 Active   Cfg. VSANS           Switch-Name    


-------------------------------------------------------------------------


  1  20:00:00:0d:ec:f0:12:40     yes     yes  20,30                          


  1  20:00:00:0d:ec:f0:11:00 *   yes     yes  10,30    

these two switches are located at two different facilities, about 15 miles apart, connectivity is provided via DWDM.  There is a VMAX array at each site and they need to be able to SRDF to each other so we need to make sure RDF adapters can talk to each other. RDF ports at site A are in VSAN 20 and in VSAN 10 at site B. So to provide communication between these two distinct VSANs we create a brand new VSAN 30 on both switches that will merge and create this "virtual" bridge between these two switches.  VSAN 30 is called "transit" VSAN. When we define IVR topology we specify what VSANs can travel on top of this virtual bridge. So I like to clean up while this bridge is still online where i can clearly see what is what and where, personal preference.

Best practice is not to merge fabrics that span multiple datacenters. If my DWDM link starts flopping and I have one VSAN, it will impact systems at both locations. With transit VSAN systems at both locations are isolated and it may impact RDF traffic. You don't want fabrics to start merging and un-merging ..flip flop is not good.

How about interconnecting 2 different fabrics through two switches (one at the edge of each datacenter) and just having the same VSAN for the interconnection link with FCIP. In that case I wouldn't need IVR and at the same time I could have DR, don't you think?

I am not sure i understand your questions. As you know a device can only belong to one VSAN so if you need to connect devices that are located at different location, you need to merge VSAN. It's one thing if you are merging a VSAN that contains RDF ports only, if it happens to flop it will only impact those ports. But let's say you have a VNX where its MirrorView port is used for host connectivity and later on you decide you need to setup replication. You need to get MirrorView port in site A to talk to MirrorView in site B but you don't want to merge those VSANs because they contain hosts. By using IVR you can keep that MIrrorView port in its current VSAN yet allow it to communicate over the transit VSAN to MirrorView port in site B.