I have an IBM blade running RHEL 5.4 server, connected to two Hitachi SANs using common fibre cards & Brocade switches. It has two volume groups made from old SAN LUNs. The old SAN needs to be retired so we allocated LUNs from the new SAN, discovered the LUNs as multipath disks (4 paths) and grew the volume groups. We then moved the logical volumes and removed the old LUNs from the volume groups.

On the next boot, the volume group was not active when the filesystems tried to mount. The output from vgdisplay -v showed LV Status : Not available for every LV in the VG.


Panicking a little, I managed to find a tenuous suggestion to force the volume group on-line. This I did with vgchange -a y vgname and after that all the filesystems could be mounted.

PHEW!

The next boot did the same thing, so again I forced the VGs on-line & mounted everything. I then wrote to Red-Hat. They suggested I alter /etc/fstab to add an option _netdev as an option for each filesystem. It worked, which is great but I just don't get it

Their explanation is: The last line says that it's doing the manual tasks I performed so I understand what it does, but I'm confused on a few things that RH don't answer (issues solved, ticket closed!):-We don't auto-start the Oracle databases on this server, although we do for other servers. Might this workaround upset these or any other /etc/rc.d/..... scripts.


Just trying to understand

Robin