LUN MAP in the WebPAM Pro: Necessary? Useful?

[JesusAli]

Hello Everyone,

I have an E and an J, and have used the Apple Scripts to make an Xsan whose main Volume uses 4 LUNs made of 6 disks each.
We have 2 MDC's, and 17 Client stations, 15 of which only have 1 SFP. We use two QLogic 5600 fiber channel switches


I have worked through the "Bullet Proof Zoning" guide posted here on Xsanity to setup my QLogic switches so that there is no Fiber Channel "crosstalk" between the client stations.
Each station only sees the Promise Storage, it doesn't see any other station.

But I am confused about the Promise WebPAM Pro interface.
Under the Subsystem icon in Tree view, under the Administrative Tools, under Storage Services, there is a tab labeled: "LUN MAP".

So, my question:
In my relatively simple Xsan, is there any reason or benefit for me to utilize LUN MAP ?

Should I hide the MDC LUN from all Client Stations? Is that necessary? Doesn't seem to me like the Clients would be trying to write to the MDC LUN.
If I was using 1 Promise to provide storage to TWO Xsan's I could see why you would want to LUN MAP some storage way from some Initiators.


Remembering that I am using Fiber Channel Zoning, Can anyone tell me anything I'm missing by not using the "LUN MAP" or "Initiators On Fabric" web interface options for my basic Xsan?

Thanks, everyone.

[abstractrude]

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

if you are using xsan no.

[JesusAli]

Yes, I'm familiar with what it does, I just didn't see how it fit into Xsan.

In what types of applications would you use the LUN MAP feature in the Promise VTrack?

[matx]

It may be desirable to use LUN mapping to carve out a piece of your VTrak for a Final Cut Server box to use as a proxy drive, or as an archive device.

[JesusAli]

thanks matx. but out of curiosity, is that preferable to making a Volume in Xsan from a single LUN and using setting Affinity for it on the FCS Device Folders?

I've read about FCS but haven't installed it yet.

[abstractrude]

if you are using xsan do not use this feature. if you have 3 servers that all need some fibre storage DAS of course, create a lun then carve it into 3 pieces and send those pieces to each server. or you can create 3 luns. the point is that you can use this technology to make sure certain servers see only certain targets.

[JesusAli]

Aha! Thanks, abstract!