SAN zone configuration

[manureano]

Hi, we've just changed from a SCSI library to a fiber one.
Now we're planning how to make the zones in the SAN switch for the TSM server and the drives, and we would like some advice.

We've got 6 drives, and the server's got 3 HBAs. We've planned to make 3 zones (zone1, zone2, zone3), each zone with a HBA and 2 drives.
We're not using yet LAN-free backup clients, but we're planning to do so. What we're planning is to add each client to 2 zones (zone2 and zone3).
This way each LAN-free client sees 4 drives, and the drives in zone1 are dedicated to the TSM server and cannot be used by the LAN-free clients.

Is this a good configuration, or would you do something different?

Thanks

 

[nbs03]

Reano,
You should have 2 independent fabrics each running on different fabric switches (A-B fabrics). If this is the case, place 3 drives in each fabric and one HBA on each fabric (you will have one left over). Zone the 3 drives to the HBA.

If you are using AIX and TS1120 drives with dual ports, you can attach drives 1,2&3 port 0 to fabric A and port 1 to fabric B, Attach drive 4,5&6 port 0 to fabric B and port 1 to fabric A. Zone all 6 drives to each HBA on each fabric.

On the AIX TSM server install the Atape drives and set up redundant tape devices using the following OS command:
'Chdev -l rmt5 -aaltpathing=yes'

With this configuration, you only define the primary /dev/rmtx devices to TSM and the Atape driver takes care of failover.

Cheers,
Neil

 

[buki]

This sounds more like TSM planning question, not SAN question. Maybe it would be better to ask on a TSM forum?

 

[dig1tal]

So would it be a best practice to have a zone for each tape drive or have 1 zone with 3 tape drives and the hba?

 

[Harry_Redl]

Hi,

general rule is to have zones configured "1 Initiator + multiple targets"
Having 1I+1T relationship is not a bad way but it is hard to manage in large numbers.
Another rule is to split tape (streaming) and disk (random) traffic. As disk traffic can easily re-send data when any packet is lost, streams usually fails ... So it is good to have these two types of traffic separated (physically) on the SAN(s) - if possible (and affordable).

Harry

 

[dig1tal]

Harry,

Thanks for the reply and insight.

 

[Jeff_Jeske]

We have four HBA's port zero of each HBA is zoned to storage. They are split between fabrics....one to fabric A and one to fabric B.

Port one of each HBA goes to each tape fabric. Those are split across drives.... one goes to drive 1,2,3 and the other goes to 4,5,6. One of the main reasons they are split is because EMC powerpath cannot load balance tape funtions.

 

[dig1tal]

Are there any documentation or websites that discuss zoning (tape drives and disk drives) for TSM? I didn't see anything in the TSM manuals (which I expected).