Ubuntu – How to Run fsck on Root Filesystem Remotely

I would guess that the Ubuntu Server LiveCD is using busybox or a very minimal ash setup - fsck may not be available. I tend to find a "desktop" LiveCD/LiveUSB very handy for such situations, either Ubuntu Desktop or a "rescue" distro like Parted Magic; sometimes both, depending on exactly what you need to do to the system in question.

The exact method depends on how you have setup luks, and if you have LVM on top of luks or if you just have a filesystem within the luks volume.

If you don't have LVM in addition to luks then you would probably do something like this.

cryptsetup luksOpen /dev/rawdevice somename
fsck /dev/mapper/somename

# or

cryptsetup luksOpen /dev/sda2 _dev_sda2
fsck /dev/mapper/_dev_sda2

If you used the LVM on LUKS option providied by the Debian/Ubuntu installer, then you'll need to start up LVM. So vgchange -aly after opening the encrypted volume, then run fsck against the /dev/mapper/lvname.

(If commands are missing, you may need to do apt-get install cryptsetup first. Similarly if you need vgchange do apt-get install lvm.)