/var/lib/docker/overlay2 eating up all disk space

Community Containers
1

Hello,

A few months ago I’ve setup Greenbone Community Container Edition with Docker successfully on Ubuntu 22.04 LTS.

All worked well until now but I haven’t used GVM for quite a while.

Now I wanted to use GVM again but saw that my complete hard disk has ran out of space.

I found out that the folder /var/lib/docker/overlay2 is eating up all my disk space.

What happened here and how can I free back disk space again?

Can I simply delete the content of the folder /var/lib/docker/overlay2?

Thanks for any help.

2

Hi,

docker sadly keeps all images when pulling new ones. Therefore you need to do cleanups from time to time. The command to remove old images is docker image prune -f.

To drop all content generated by our container images you can run

export DOWNLOAD_DIR=$HOME/greenbone-community-container
docker-compose -f $DOWNLOAD_DIR/docker-compose.yml -p greenbone-community-edition down
docker container prune -f
docker image prune -f
docker volume prune -f

Please keep in mind that the last command docker volume prune -f will delete all stored data. You will loose all you users and scans.

2 Likes
3

Hello,

thanks for your quick reply.

I assume that mainly the data container with the definitions which I pull once a day using a cron script are causing this behavior, right?

So another cron script with the docker image prune -f command for housekeeping should do the trick …

Can I execute docker image prune -f while the Greenbone containers are running?
Do I have to (or can) run this command as root?

4

Just take a look at your current images docker image ls. Older ones should be listed there too. If you pull a new version of an image docker keeps the old one. especially if a container using this image is still running.

Yes docker prune just removes unused and untagged images. If an image is still used in a container it keeps it. That also means after pull you need to restart the containers and then run prune.

I am sorry I can’t answer that question because it depends on your docker setup. The user needs to have access to docker’s unix domain socket.

1 Like
5

Hello @bricks

Thanks for the explanations which helped freeing back the disk space.

But running out of disk space seems to have broken something with the redis container …
I’ll create a new topic for this …