Linux LVM on MD raid problem with recovery
Posted: 18 Jul 2012, 23:16
Hello,
due to unknown reason my md based raid5 on 3 drives got corrupted. one drive just went out from the group (and in fact was showing all ok when i was trying --examine it). So I removed all partitions from that drive (as i couldn't re-enable or re-add it to the md group) and just re-added to md group using mdadm. Unfortunately during rebuilding my PC just stopped responding. I had to reset it. After that i couldn't even start my raid with 2 working previously disks, so i decided to recreate the md structure. Mdadm discovered that these two discs (which were ok) are part of the same group, so i formed up raid 5 with 2 partitions only, and then added corrupted one. All got rebuild, but i lost my lvm structure which was on top of md (one vg + a few lvgs). All standard tools coming with lvm were not showing any info about lvm groups on my md.
I was trying to use TestDisk 6.13 to see if i can find any sign of LVM on my recreated md volume. I took option none for partition type, but see some strange results - only HFS and FAT12 (I don't know what it could be), but no LVM information. Am I proceeding correctly and it means i lost all data (a few 100s MB very important)? Or there is other way i should try?
Thanks in advance for any help.
Best regards,
MCC
due to unknown reason my md based raid5 on 3 drives got corrupted. one drive just went out from the group (and in fact was showing all ok when i was trying --examine it). So I removed all partitions from that drive (as i couldn't re-enable or re-add it to the md group) and just re-added to md group using mdadm. Unfortunately during rebuilding my PC just stopped responding. I had to reset it. After that i couldn't even start my raid with 2 working previously disks, so i decided to recreate the md structure. Mdadm discovered that these two discs (which were ok) are part of the same group, so i formed up raid 5 with 2 partitions only, and then added corrupted one. All got rebuild, but i lost my lvm structure which was on top of md (one vg + a few lvgs). All standard tools coming with lvm were not showing any info about lvm groups on my md.
I was trying to use TestDisk 6.13 to see if i can find any sign of LVM on my recreated md volume. I took option none for partition type, but see some strange results - only HFS and FAT12 (I don't know what it could be), but no LVM information. Am I proceeding correctly and it means i lost all data (a few 100s MB very important)? Or there is other way i should try?
Thanks in advance for any help.
Best regards,
MCC