Hi.
I just had a weird problem I'd like to share, and see how it can be fixed.
After installing dozens of servers without a problem, one specific
install failed during setup-storage. The error looked something like this :
> Executing: fai-vol_id -u /dev/sda1
> Executing: fai-vol_id -l /dev/sda1
> /dev/sda1 UUID=6eb8e204-614f-42f1-9431-5b2aacf091d4
> Executing: fai-vol_id -u /dev/sda2
> Executing: fai-vol_id -l /dev/sda2
> /dev/sda2 UUID=c480d5e4-3271-4d93-8875-12dacaa032d1
> Executing: fai-vol_id -u /dev/system/swap
> Command had non-zero exit code
My config file looks like this :
> disk_config disk1 fstabkey:uuid
> primary /boot 256 ext3 rw
> primary / 512 ext4 rw
> primary - 0- - -
>
> disk_config lvm
> vg system disk1.3
> system-home /home 1000 ext4 noexec,nodev,nosuid
> system-usr /usr 2000 ext4 defaults
> system-tmp /tmp 1000 ext4 nodev,noexec,nosuid
> system-var /var 5000 ext4 noatime
> system-swap swap 2000 swap -
It seems fai-vol_id could not probe /dev/mapper/swap. A quick tested
showed it worked fine with the other LVs on the disk.
After investigating more, it turned out that there used to be on the
disk, at the same place, a ReiserFS filesystem. I actually found out the
following :
> root@fai-client:~# blkid -p /dev/dm-*
> /dev/dm-0: ambivalent result (probably more filesystems on the
device, use wipefs(8) to see more details)
> /dev/dm-1: UUID="f0d3e822-90d2-418a-af56-0228db0c600e" VERSION="1.0"
TYPE="ext4" USAGE="filesystem"
> /dev/dm-2: UUID="d76feba3-af3b-4278-8344-eeccb6e4d34c" VERSION="1.0"
TYPE="ext4" USAGE="filesystem"
> /dev/dm-3: UUID="0b180c48-d8d5-4008-bd5d-b48dc456d5d0" VERSION="1.0"
TYPE="ext4" USAGE="filesystem"
> /dev/dm-4: UUID="6ad447dc-7df4-40b8-81ef-d852b5d6e714" VERSION="1.0"
TYPE="ext4" USAGE="filesystem"
Wipefs revealed that it could see two filesystems :
> root@pdf:~# wipefs /dev/system/swap
> offset type
> ----------------------------------------------------------------
> 0x10034 reiserfs [filesystem]
> UUID: fab7a960-4570-44a9-a74f-e02429213e6a
>
> 0xff6 swap [other]
> UUID: ad03f0b0-b2cc-4908-96ca-e8f77ad1522b
A quick "wipefs --all /dev/system/swap" fixed the issue, and
setup-storage then ran fine.
Now, on to "how do we fix this issue ?"
I see several ways this could be done :
- add a "wipe" action that should be run before an install, booting
something like DBAN through PXE, and wiping everything.
- before destroying any partition/vg/other, perform a "wipefs --all"
on it.
I like the second solution better, though.
--
Vivien Bernet-Rollande
Systems& Networking Engineer
Alter Way Hosting
