I am running a Windows 2003 server on a
. I'm using two QLogic 2300 HBAs connected to the IBM 2109-F16 switch and an IBM 4560SLX tape library using a FCO (
Option) card in the library. The FCO card is connected to the IBM 2109-F16 switch. I have port-zoned the server and the library in one zone. I cannot write to tapes with this setup. I'm getting device errors, communication errors and then the drive is taken offline. But if I remove the FCO cable from the IBM 2109-F16 switch and plug it directly into the HBAs on the server, it will write to the tapes. What am I missing?
It is usually best practice to use a separate HBA in the fabric for tape access. Doing so keeps streaming tape traffic separate from standard disk traffic in the SAN. You can zone out the tape HBA with the tape port on the switch, which will decrease the impact of tape reset/rewind issues from your disk traffic. Also, make sure your tape library supports the FC-SW (Fibre Channel Switched) protocol, and is not FC-AL (Fibre Channel Arbitrated Loop) only. If your tape library is FC-AL only, you still have options. Since the IBM 2109-F16 is actually a re-branded Brocade switch, you may be able to use the Brocade "QuickLoop" feature to attach the tape drive to a QuickLoop port on the switch.
In either case, I would still keep disk and tape traffic separate, as indicated in the picture below:
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