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It’s funny that I got my start working with HP systems, first HP-MPE, then HP-UX, because I hate HP these days. HPUX is still the only operating system that can’t tolerate something as simple as a switch migration.

HPUX is still, to this day, dependant on the /dev/dsk/cxtxdx numbering in it’s volume groups.  Unlike all *REAL* Logical Volume Managers, HPUX doesn’t write any sort of PVID to the disk, doesn’t store the disk configuration for later use.

So what happens is, if the D_ID (Destination ID) of the port changes, HPUX will generate a new cXtXdX number, and all existing volume group configuration will be lost.

So what you have to do – gather the volume group configuration using ‘vgdisplay’ and ‘syminq’ before you start.   Deactivate the volume group and export it.

Once you’ve moved the cables, and rezoned, rescan the bus and run ‘insf -e’ to build the new special files.

Run the ‘syminq’ again and use the information you get there (new symdev –> cXtXdX number)  to rebuild and reimport the volume groups.  Reactivate the volume groups and ensure everything is present.

Reboot the system and all should be good.

What’s pretty pathetic is that even Windows can handle such a simple change, Solaris doesn’t care about the port #’s, AIX cares, but the simple process of removing and rebuilding the devices in the ODM fixes that, because the AIX LVM is dependant on the PVID of the disk, not the device number.

It just seems like something that would have been so simple to fix, so long ago….