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I setup a new email server today and I did lvm for the main drive and then LVM for /opt.

I realized I did not give myself enough room for /opt so I decided to try and extend it and I must of screwed up the instructions because on reboot I get some errors.

it does find both lvm groups (found volume group opt using metadata type lvm2 and found volume group (myhostname) usint metadata type lvm2) then it says: fsck.ext3: bad magic number in super-block while trying to open /dev/opt/opt the superblock could not be read or does not describe a correct ext2 file system etcetc.

I did try to manually scan it but it does not work. the issue is with sdb//dev/opt/opt

fdisk -l /dev/sdb

Disk /dev/sdb: 64.4 GB, 64424509440 bytes 255 heads, 63 sectors/track, 7832 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Disk identifier: 0x00babcaf

Device Boot Start End Blocks Id System /dev/sdb1 1 7832 62910508+ 83 Linux

PVscan: zimbra:~# pvscan PV /dev/sdb1 VG opt lvm2 [40.00 GB / 96.00 MB free] PV /dev/sda2 VG hostname lvm2 [39.75 GB / 0 free] Total: 2 [79.75 GB] / in use: 2 [79.75 GB] / in no VG: 0 [0 ]

lvscan: lvscan ACTIVE '/dev/opt/opt' [39.90 GB] inherit ACTIVE '/dev/hostname/root' [38.08 GB] inherit ACTIVE '/dev/hostname/swap_1' [1.68 GB] inherit

vgscan Reading all physical volumes. This may take a while... Found volume group "opt" using metadata type lvm2 Found volume group "hostname" using metadata type lvm2

any ideas on how I can get this fixed? the data is not super critical but rather not start over


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It doesn't seem like you have an LVM problems. Could you perhaps describe how you extened the LV/File System? – katriel Jun 19 '10 at 21:23
Now you know why you should always make a backup before fiddling with partitions. – John Gardeniers Jun 20 '10 at 0:10
up vote 0 down vote accepted

yeah :) I did have a backup though, but I had done a few changes. I followed a guide and I had done one big mistake, when I first setup LVM I did not fdisk my drive into sdb1, so I created the LVM right on sdb and I think when I created sdb1 after giving the drive more room it causes the original stuff to poof.

still learning LVM.

either way I am all good now, I just started over, used my backups and voila.

thanks though.

share|improve this answer
From what you say, the partition table overwrote part of your LVM / partition data, which is a pretty serious problem. You might have recovered some data, but it almost certainly would be faster to start over. – Slartibartfast Jun 20 '10 at 23:08

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