Hi, Can I set thing that my instance will fsck disk when boot system?
I can not find the tutorials about this 
1 Like
That doesn’t seem to be something LXD related.
However you can configure for which devices fsck will run during boot using the sixth column in the /etc/fstab file. There are more details here in the man page of the corresponding systemd-fsckd service that will trigger those checks on a recent Ubuntu system using systemd: https://www.man7.org/linux/man-pages/man8/systemd-fsck.8.html
thank you, I will try it!
Note: When you run fsck while the PC is open, it will write this message:
The filesystem is mounted. If you continue you WILL cause SEVERE filesystem damage.
Contents of /etc/fstab:
# /etc/fstab: static file system information.
#
# Use ‘blkid’ to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
#
# / was on /dev/sda8 during curtin installation
/dev/disk/by-uuid/05c25a3d-c01c-43ae-a848-9932c64df6fd / ext4 defaults 0 1
# /boot/efi was on /dev/sda2 during curtin installation
/dev/disk/by-uuid/9AAB-377A /boot/efi vfat defaults 0 1
/swap.img none swap sw 0 0
It’s recommended that you don’t do so. Because that’s would be reduandant system checks (which may corrupt the filesystem) When the PC says:
/dev/sdaX: Recovering journal
…
…
…
…
/dev/sdaX: Primary superblock features different from backup. Check forced.
That would be necessary then to do checks.
Hi, I have hundreds of instances in my LXD cluster.
When the host crash, I need to fsck instances on this host manually.
It seems that I can not exec fsck command automatically, because I don’t know the uuid of disk when I build the base image of instance.
I use lxd container instead of virtual machine.
Is there any way to exec fsck command?
When file system of container breakdown, I can not expand instance disk size online successfully.
I need to exec command manually. So I want instance exec fsck before system boot. 
sudo rbd map -p lxd container_shpc-168-instance-WvycKBTn
sudo fsck.ext4 -y /dev/rbd0
sudo resize2fs /dev/rbd0
sudo rbd unmap lxd/container_shpc-168-instance-WvycKBTn
rbd showmapped