Hello, we have a wierd and urgent problem, with a few of our p595 LPARs running AIX 5.3. The LPARs ran AIX 5.3 TL 7 and booted off EMC SAN disks, using EMC Powerpath. Every boot we run "pprootdev on" and "pprootdev fix". We can issue "bosboot -a" and we can reboot the machines.

Now, on two occasions, right after the update to AIX 5.3 Technology Level 9, Service Pack 3 the system fails to reboot. When starting the partition to the SMS menu you can see the correct (rootvg) devices being scanned, but the devices are NOT listed as a possible boot device.

When booting off a NIM server and trying to restore an mksysb, the entire rootvg (all disks in it) is invisible and cannot be selected. Some user-defined volume groups are also "missing".

When giving the partition access to a 'new' EMC disk, this new disk shows up and can be used to restore the mksysb. When that is complete, the original disks show up properly (using lspv etc.) and seem perfectly alright.

Anyone ran into this same problem? Any idea's, suggestions, fixes??

Being able to see a device but being unable to access the data area sounds like a SCSI disk reservation problem.

Thanks for your suggestion. It indeed was a SCSI reservation type of problem. Related to a nondisruptive EMC code upgrade. EMC is looking into it.