vg00 mirror question.

[Ray Herbig]

My question is similar to one posted earlier. A guy had added a new physical volume to increase /home. I'm facing the same issue but I didn't see an answer in the responses. Basically, I have two disks in vg00. One mirrors the other. /usr is running out of space and the physical volume its mounted on is also out of space. The other pv has about 133 free pe's. If I introduce another drive into the vg00 mix, and extend /usr. Am I correct in saying that I could only extend it by 133 pe's, and that I would have to remove the mirror for that lv if I extended it beyond 133 pe's.

Thanks,
ray

[Edward Sedgemore]

Yes, your exactly right. Youve worked it out correctly.

The thing to do is add the 3rd disk, break the mirrors for some of the other volumes and remirror them to the 3rd disk, this frees up space on Vol B (Vol A is primary, Vol B is mirror, Vol C is new disk) and allows you to extend /usr from Vol A to vol B then mirror it later to the new Vol C which has plenty of space on.

[Denver Osborn]

In the current setup, if you have 133 free PE on one and 0 PE on another disk. Adding a 3rd drive to the VG the most you'd be able to extend a mirrored lvol is by 133 PE. To extend the MIRRORED lvol beyond that all it'd require is another drive added to the VG. As long as there are free PE on both sides of the mirror it should be fine. This was assuming you aren't using lvm pvgs.

-denver

[Christopher Caldwell]

Don't know how many total disks you have, but you can always try something like moving home to another vg.

# bdf /home
Filesystem kbytes used avail %used Mounted on
/dev/vg02/home 524288 504782 18694 96% /home

Make the new volume group on the new pv. Make a logical volume with a file system like /home.new

cd /home
find . | cpio -pdxm /home.new
umount /home
umount /home.new

mount /dev/newlvol /home

edit /etc/fstab to remove modify the entries for /home and /home.new

Remove the old home lvol. Boot in single user mode. Increase the size of var, usr, whatever.

[Mark Mitchell]

Disk is cheap, I would recomend getting 1 more and migrate off the old disks. Otherwise you are going to have to deal with this again at some point.