Christian Wahlgren spake the following on 10/19/2006 11:22 PM: > On 10/18/06, Jay Leafey > <jay.leafey at mindless.com> wrote: >> I just finished playing this "game", though with a SAN volume. It >> took a couple of steps to take advantage of the extra space. >> First, the SAN manager extended the volume from 100G to 200G. I idled >> everything referencing the drive by disabling the volume >> group ( vgchange --available n vgname ). I then ran fdisk against the >> volume, noting the starting cylinder of the only partition on >> the drive. I deleted the partition, recreated it using the same >> starting cylinder and let fdisk figure out the last usable cylinder >> on the drive, reset the partition type to LVM, and wrote the partition >> table. At this point I had to reboot to get the system to >> re-read the partition table. Once it came back up I used pvresize to >> extend the physical volume to use the additional space in the >> partition. After that, vgdisplay showed the additional space as >> available for allocation. This was complicated by the fact that it >> was actually a two-node cluster (RHCS and GFS) so I had to reboot both >> nodes before running pvresize. >> >> I was originally just going take the easy way out by creating a second >> partition/physical volume to use the additional space, but it >> seemed inelegant. I'm unlikely to ever extend this LUN more than >> once, but you just never know! > > Hi and thanks for letting me know that I'm not the only one with this > situation. And as it seems there is no straightforward and recommended > way to do this. > > I have experimented and practiced a little with a CentOS installation > on VMware to see that both ways of doing this will work. During the > last couple of days I've been backing up my volume for safety. > Probably on Sunday I will use my practice and I will post my exact > steps. > > Although a bit "raw" I still prefer editing the original partition (as > described above) than adding extended partitions when you grow you > "exported disk" (and I most probably will add more disks to my RAID5 > volume in the future). Then you always have a simple and clean > partition table. > > I also think this scenario should be mentioned in the LVM Howto > "Common Tasks", and the two (as I know) ways of doing this. Or is this > scenario very uncommon? > > Regards, Christian Maybe it was uncommon when the howto was written, but with newer raid controllers that allow you to expand the array by adding drives, this will become more common. I also was experimenting in VMWare, and I had a problem expanding the PV after I expanded the raid partition. But then I was experimenting by increasing the array with one larger drive at a time, and letting the array re-sync until I had 3 drives all larger (software raid). I used fdisk to expand the LVM partition on the raid drive, but couldn't expand the LV. Maybe I did it wrong, but then thats why I was using vmware. Next week, I'll go at it again. -- MailScanner is like deodorant... You hope everybody uses it, and you notice quickly if they don't!!!!