premise: on same hw environment and WIndows 2003 we've never got this issue.
We have some Windows 2008 R2 (64bit) running with several FC LUNs mapped on a 3160 cluster filer.
Host has three HBA QLE2460, two of them are zoned and mapped to the NetApp storage while the third one is mapped on another zone to see the FC tape library on the SAN and to perform backups, this last HBA is zoned/mapped to use two LTO FC tapes.
Host has installed the last and right FC host utilities 5.3, Snapdrive 6.3 and MPIO 3.4.
From which concern availability of storage there are no problems and both managed from MPIO datapath works fine. The issue is with the 3rd HBA.
In the MPIO MMC I see (rightly) only the first two HBA, the only ones connected to filer's LUNs.
In the device manager I can see all the three HBA
Running Sansurfer (the Qlogic utility) I can see all the three HBA and below each of all I can see all the LUNs and below the third I can see the two tapes drive.
ISSUE. Under the device manager I cannot see the two tapes, system does not see the tapes and I cannot perform backups-
This has never happend in an identical hw configuration but running on W2K3.
Again. One of these servers has been upgraded from W2K3 to W2K8. Alla applications continue to run with no issue, LUNs that are visible and managed before still continue to work...tapes are disappeared!