When I was encountering this problem, I could not build the job. Jenkins shown this warning message Your Jenkins data directory /var/lib/jenkins (AKA JENKINS_HOME) is almost full. You should act on it before it gets completely full.
I checked the disk space and here it shows:
admin@thachhoang:~$ df -h
Filesystem Size Used Avail Use% Mounted on
udev 16G 0 16G 0% /dev
tmpfs 3.2G 1.7M 3.2G 1% /run
/dev/sda2 197G 197G 0G 100% /
tmpfs 16G 20K 16G 1% /dev/shm
tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs 16G 0 16G 0% /sys/fs/cgroup
/dev/loop0 92M 92M 0 100% /snap/core/8689
I found out the reason is that there are a lot of dangling images generated with ID and tag <none> which caused disk space problems.
These dangling images are produced as a result of docker build or pull command. more detail explanation here
admin@thachhoang:~$ sudo docker image ls
REPOSITORY TAG IMAGE ID CREATED SIZE
frontend latest f4ff7e585249 3 hours ago 74.5MB
<none> <none> df960ce8afd8 3 hours ago 74.5MB
<none> <none> 8ffb0de2aef9 5 hours ago 2.69GB
<none> <none> 5aef9689ebb3 5 hours ago 2.53GB
<none> <none> 90c914fcaaf0 7 hours ago 74.5MB
backend-payment latest 2403e4ca333d 12 hours ago 310MB
<none> <none> ad6fc261739a 33 hours ago 319MB
<none> <none> 2d00312d4e71 33 hours ago 1.75GB
<none> <none> 44ffe53cc491 41 hours ago 2.28GB
<none> <none> edf28e9d9edf 42 hours ago 2.58GB
<none> <none> 058e82ceb897 42 hours ago 2.57GB
<none> <none> 9abf902cc5a1 2 days ago 1.75GB
<none> <none> 637639ef34b2 2 days ago 2.28GB
The below command can be used to clean up these dangling images:
docker rmi $(docker images -f "dangling=true" -q).
Or use this one if you see any permission denied.
sudo docker rmi $(sudo docker images -f "dangling=true" -q)
In addition, you should enable “Discard old builds” option in all Jenkins Jobs configuration to save the space.
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