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I'm looking at zoning 2 FC switches which were not zoned when initially implemented for some reason. They are IBM/Brocade switches and I've found this page to be quite helpful.

I'm just trying to figure out whether to use the WWN or WWPN when adding devices to a zone. I understand that the WWN identifies a device and the WWPN a specific port.

In simplified form lets say I have:

  • 1 host/WWN with 2 HBAs/WWPNs, and
  • 1 storage array/WWN with 2 FC ports/WWPNs.

In English, I would say "grant host1 access to storage1", so does that mean I just use the WWNs in the zone definition?

Is there a reason why using the WWPNs is preferable?

Should I just use both?

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up vote 1 down vote accepted

On my Brocade fiber switch I guess I use the WWN and create an Alias. Are you creating the Alias to associate?

The basics are

  • 1)Create a new Alias (1 for each HBA since you will multi path) (HBA_1_A, HBA_1_B)
  • 2)Find the WWN you want for one of the Aliases ,HBA_1_A, in member selection, add the member
  • 3)Click the Zone tab, create a new zone
  • 4)expand the aliases list, and add the HBA_1_A and the SP of the SAN you want to connect
  • 5)Click the Zone Config tab, expand zones, add members to the zone config

Not sure if the helps in any way.

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I thought the WWN was the for the HBA, and the WWPN was the PORT on the HBA. That way you could if you wanted to zone by ports but the WWN encompasses both. So... your mileage may vary. I say keep it simple.

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I'm a Cisco MDS-guy myself sorry so don't have much Brocade experience but almost certainly it's the WWN's you'll care about when building an ISL (which is what it sounds like you're doing). The reason is that the WWPN is really only relevant inside a device as it's the key value used in most host tables, i.e. it's of little use outside a device - does that make sense?

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I read wikipedia's blurb on ISL... I don't think that's relevant to what I'm doing. I do have 2 switches, but they aren't linked. Basically what's been done is that each host or storage array has 2 FC ports, 1 connected to each switch. Now I'm adding zoning on the switches so that hosts can only see the storage that they need to see, because at the moment there's no zoning and there's a risk that storage could be mounted on a host that shouldn't be accessing it. – ThatGraemeGuy Feb 18 '11 at 11:09
Ok, still not clear why you're linking them if not setting up an ISL to be honest. Can't your array do per-host presentation? that would remove any chance of mispresentation. It's funny actually, Cisco being Cisco their SAN switches come set to what is in effect a 'deny-deny' mode, you have to manually build the connection from one host to one target and back again, seriously tedious but secure. Many of the other SAN switches I've used do this the other way where you have to pull back connectivity from everything being open. Just different approaches really I guess. – Chopper3 Feb 18 '11 at 11:43

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