Ubuntu

Get rid of full disk in Ubuntu

by mounting directory appropriately.

Recently when working with docker-compose, I met an issue:

No space left on device

The first solution comes up to my mind is add disk space from different partition to the partition that holds docker. But this is difficult. Turns out we have easier problem that we can mount the directory that holds docker data to different directory.

Check the /var/lib/docker, we will see that it belongs to /dev/sdb3

user:/var/lib/docker$ df .
Filesystem     1K-blocks     Used Available Use% Mounted on
/dev/sdb3       58795996 53734356   2045244  97% /

And /dev/sdb3 is about to full.

Check the home directory

user:/home$ df .
Filesystem     1K-blocks      Used Available Use% Mounted on
/dev/sdb4      892956360 429285640 418241268  51% /home

/dev/sdb4 still has a lot of space. So we will mount /var to this home directory.

This is how we could do that

• mkdir -p /home/var
• rsync -va /var /home/var
• mv /var /var.old # you can remove /var.old when you are done to reclaim the space
• mkdir -p /var
• mount -o bind /home/var /var
• update your /etc/fstab to make the bind-mount permanent.