Wednesday, 22 November 2006

Brocade on the up

Brocade shares were up 10.79% today. I know they posted good results but this is a big leap for one day. I wish I hadn't sold my shares now! To be fair, I bought at $4 and sold at $8 so I did OK - and it was some time ago.

So does this bode well for the McDATA merge? I hope so. I've been working on Cisco and the use of VSANs and I'm struggling to see what real benefit I can get out of them. Example: I could use VSANs to segregate by: Line of Business; Storage Tier; Host Type (Prod/UAT/DEV). Doing this immediately gives me 10's of combinations. Now the issue is I can only assign a single storage port to one VSAN - so I have to decide; do I want to segment my resources to the extent I can't use an almost unallocated UAT storage port when I'm desperate for connectivity for production? At the moment I see VSANs as likely to create more fragmentation than anything else. There's still more thinking to do.

I'd like to hear from anyone who has practical standards for VSANs. It would be good to see what best practice is out there.


Anonymous said...

A few thoughts on VSANs --

Just because you put a particular storage port on a VSAN doesn't mean that it can't talk to initiators on other VSANs. Inter -VSAN Routing allows you to create zones the span VSANs, so you can have an initiator in one VSAN zoned to a target in another VSAN.

VSANs are also great for cases where you want to ISL two separate fabrics, but don't want to deal with merging zones. You can route between the VSANs across ISLs without merging the zonesets.

Also, if you're extending your fabric across a WAN link (say with FCIP), you can create a separate VSAN on each side of the WAN and route between them with IVR.. instead of having a single fabric spanning the WAN. That way your fabric doesn't segment when the WAN goes down, and you're not broadcasting RSCNs across the WAN when you make fabric changes.

Anonymous said...

I get disappointed at Cisco bagging when it seems obvious that people don't know the power of the MDS switches. IMHO, Brocade has lots to catch up on. One thing in particular about VSANs is that each one runs its own services which protects other VSANs from interference. Eg, each VSAN runs its own FCNS. Now if your Brocade fabric took a dive and the FCNS got totally screwed up, there goes the fabrics method of knowing where to send its data. Each VSAN also has QOS, in order delivery and FSPF load balancing. Upcoming enhancements to the MDS mean that you can directly plug DWDM SFP's (4 and 10Gbps) into the switch. Currently, you have CWDM at 2 Gpbs. I can create trunking port channels per individual or multiple VSAN's over those new SFP's and give me huge native fibre channel extensions. The list goes on when it comes to VSAN's

Now, what can I do with a Brocade switch? Hope that nothing goes wrong with it.

My advise is to do Cisco MDS training and then reconsider why you would use VSANS.