Questions[zoning](server)

I've been working with the storage guy in our business and I'm trying to get up to speed on zoning, but I'm finding conflicting information. I'm confused about the relationship between hard and soft zones, and WWN and port-based zones.

Here's what I thought was correct:

• Hard zoning is done by the switches, disallowing certain WWNs (or ports) from talking by examining source and destination information, regardless of knowledge of one another's existence. I compare this to conventional IP firewalls (only certain IPs can talk to one another - I know Google's IP but I still cannot reach it).
• Soft zoning allows everything to reach everything else, but prevents discovery of everything in the fabric by limiting what information the name server will respond with when a new HBA wants to know what it can talk to. I compare this to a DNS server that provides different responses based on the querying host - hosts can still talk if they know one another's IP address.
• WWN and port-based zoning are unrelated to the above - they simply imply how you identify members of a zone.

Here are the sites I've looked at:

http://www.emcstorageinfo.com/2007/11/san-zoning-in-details.html

http://www.sanduel.com/SAN-Storage-FAQs/What-are-Hard-Zoning-and-Soft-Zoning.html

http://www.enterprisestorageforum.com/sans/features/article.php/3710231/Storage-Basics-Understanding-Fibre-Channel-Zones.htm

http://en.wikipedia.org/wiki/Fibre_Channel_zoning

(I know that none of these are particularly reputable - sue me :) )

Some of the sites above seem to say that hard zoning and port-based zoning are synonyms, as are soft zoning and WWN-based zoning.

tl;dr: Is there any fixed relationship between hard, soft, WWN, and port-based zoning in a SAN?

In case the answer is vendor-specific, we use HP SAN equipment, specifically HP HSV450 and HP XP12000 disk arrays, with (I think) Brocade switches.

I have a single FC switch here that has a bunch of servers hanging off of it. Currently it is zoned (as per my previous question, Fibre Channel zoning best practices) by WWN, one zone for each pair of (server, disk array).

My question is, is there any reason I shouldn't do this zoning by port instead of WWN? The switch is already labeled with a server name per port, and I don't expect to do any moving of cables. I'm tending toward zoning by port because it allows me to replace an FC card without rezoning. That's not something you need to do often, you say? You're probably right, but I'm in the middle of a period where I have to do it a lot.

If it matters, it's a QLogic switch with QLogic or Brocade FC cards and a NetApp filer.

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?

I'm hoping that this will be useful for more people than just me.

Right now I've got a fibre channel switch, a NetApp filer, and some servers running Oracle. All of the servers can see the same LUNs on the filer, and there's some internal clustering magic to keep them from stomping over each other's disk. The switch is zoned such that each server is in its own zone with the disks it can see. Thus, something like this:

Zone1 = {Oracle1, NetApp1, NetApp2}
Zone2 = {Oracle2, NetApp1, NetApp2}
Zone3 = {Oracle3, NetApp1, NetApp2}

(Those are soft zones based on WWN). My question is, is this the best way to do things, or would be be better to have one zone for all the things that share resources?

Zone1 = {Oracle1, Oracle2, Oracle3, NetApp1, NetApp2}

It seems to me like those are the same thing, but maybe there's something I don't know about? It looks like a little less management overhead to do it this way. Not a lot, but a little.