I remember a friend having a similar issue with the MDS.  It turned out to be 
a switch firmware and HBA firmware mismatch "bug".  They upgrade the 
firmwares and it worked after that.

On Wednesday 20 December 2006 08:22, Krishnan, Ramamurthy wrote:
> Hello all
>
> I may be a little off topic here.. Please can anyone share any
> experiences configuring/using a Cisco FC switch (particularly a MDS9506)
> with a tape library?  We are facing a weird problem where the jbconfig
> (and sjisn) command fails not able to communicate with the robotic arm.
>
> Windows 2003 SP1 server
> Emulex LP10000-DC HBA
> Cisco MDS9506
> ATL PX720 LTO3 library
> NetWorker 7.2.1
>
> When we tried directly connecting the robotic arm (leaving the drives to
> go through the switch) to the Windows 2003 server, it works merrily.  So
> we suspect it may be something to do with the swtich/switch settings.
>
> Thanks in advance for any help.
>
> Rgds, Ram.
>
>
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