Re: [linux-lvm] /dev/vg1/dir-1: read failed after 0 of 4096 at ...

[Tero <termant@gmail.com>]

On 30.5.2012 13:10, Tero wrote:
> Hi,
>
> I really messed up my LVM settings. I am using Ubuntu 10.04 server and
> my updates were up-to-date. Here is the whole story:
>
> 1. I have got four (4) identical 320 GB hard disks: "/dev/sda",
> "/dev/sdb", "/dev/sdc" and "/dev/sdd" and one (1) 1 TB "/dev/sde".
> 2. Each 320 GB disk is paritioned to 1 GB + 319 GB ("/dev/sdX1" and
> "/dev/sdX2") and 1 TB disk has only one 1 TB parition.
> 3. There is RAID-1 (/dev/md0) on the "/dev/sdX1" paritions and RAID-5
> (/dev/md1) on the "/dev/sdX2" partions.
> 4. LVM volume group "vg1" was set at first only on /dev/md1.
> 5. On vg1 there was only logical volumes: "root", "dir-1" and "dir-2".
> 6. Later I attached hard disk /dev/sde and attached it to volume group "vg1"
> 7. I created logical volume drbd with command something like "lvcreate
> -L 800G -n drbd vg1 /dev/sde1"
> 8. I was setting DRBD device on logical volume "drbd". I made some
> changes to "filter" parameter in "/etc/lvm/lvm.conf".
> 9. I noticed that there "PV unknown device" and I accidentally removed
> it with command (I am not 100% sure of this) "vgreduce --removemissing
> vg1". If I remember correctly used switch "-f" too. :-(
> 10. Then I found out that system was acting strangely. If I remember
> correct it prompted something "Couldn't find device with uuid...". Then
> I realized how stupid I had been!
> 11. Then I followed instructions on
> "http://support.citrix.com/article/CTX116095":
>     11.1. I booted with installation disk to installation environment
>     11.2. I run: "vgdisplay --partial --verbose"
>     11.3.Then I run "pvcreate --restorefile /etc/lvm/backup/vg1 --uuid
> UUID /dev/sde1 -ff"
>     11.4. Then again: "vgdisplay --partial --verbose"
>     11.5. At last: "vgcfgrestore --file  /etc/lvm/backup/vg1 vg1"
> 12. I removed volume group "drbd".
> Notice: device /dev/sde was attached all the time.
> 13. After this running commands:
>
> # pvs
> /dev/vg1/dir-1: read failed after 0 of 4096 at 299997528064:
> Input/output error
> /dev/vg1/dir-1: read failed after 0 of 4096 at 299997585408:
> Input/output error
> /dev/vg1/dir-1: read failed after 0 of 4096 at 0: Input/output error
> /dev/vg1/dir-1: read failed after 0 of 4096 at 4096: Input/output error
> /dev/vg1/dir-1: read failed after 0 of 4096 at 0: Input/output error
>
> /dev/vg1/dir-2: read failed after 0 of 4096 at 504658591744:
> Input/output error
> /dev/vg1/dir-2: read failed after 0 of 4096 at 504658649088:
> Input/output error
> /dev/vg1/dir-2: read failed after 0 of 4096 at 0: Input/output error
> /dev/vg1/dir-2: read failed after 0 of 4096 at 4096: Input/output error
> /dev/vg1/dir-2: read failed after 0 of 4096 at 0: Input/output error
>
> /dev/vg1/root: read failed after 0 of 4096 at 14331871232: Input/output
> error
> /dev/vg1/root: read failed after 0 of 4096 at 14331928576: Input/output
> error
> /dev/vg1/root: read failed after 0 of 4096 at 0: Input/output error
> /dev/vg1/root: read failed after 0 of 4096 at 4096: Input/output error
> /dev/vg1/root: read failed after 0 of 4096 at 0: Input/output error
>
> PV    VG    Fmt    Attr    PSize    PFree
> /dev/md1        lvm2    --    891.46g    891.46g
> /dev/sde1    vg1    lvm2    a-    931.51g    931.51g
>
> # lvs
> LV    VG    Attr    LSize
> dir-1    vg1    vwi-a-    279.39g
> dir-2    vg1    vwi-a-    470.00g
> root    vg1    vwi-a-    13.35g   
>
> Is there any change to recover LVM from this point? I don't care if I
> loose the newest data but I really want to salvage at least the older data.
>
>
> Tero
>
Actually this is much like what happened to me:
http://bisqwit.iki.fi/story/howto/undopvremove/

Correction to item 9. where I claimed that I used command "vgreduce". I
am pretty sure I used "pvremove" instead as told in the article "How to
undo pvremove".


Tero