[SOLVED] How to free up space on docker devmapper and CentOS7?

Issue

I am learning docker and I am using v1.11.0 I am trying to install hadoop but devmapper is complaining about free disk space?

devmapper: Thin Pool has 82984 free data blocks which is less than minimum required 163840 free data blocks. Create more free space in thin pool or use dm.min_free_space option to change behavior

I have deleted all my images but the problem persists:

[root@localhost hadoop_docker]# docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
debian              latest              47af6ca8a14a        3 weeks ago         125 MB
[root@localhost hadoop_docker]#

and this is my disk configuration:

[root@localhost ~]# lsblk
NAME                       MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sda                          8:0    0    8G  0 disk
├─sda1                       8:1    0  500M  0 part /boot
└─sda2                       8:2    0  7.5G  0 part
  ├─centos-root            253:0    0  6.7G  0 lvm  /
  └─centos-swap            253:1    0  820M  0 lvm  [SWAP]
sr0                         11:0    1 1024M  0 rom
loop0                        7:0    0  100G  0 loop
└─docker-253:0-844682-pool 253:2    0  100G  0 dm
loop1                        7:1    0    2G  0 loop
└─docker-253:0-844682-pool 253:2    0  100G  0 dm

How can I free up the disk space?

Solution

You can use:

docker system prune -a -f --volumes

where:

• -a == removes all unused images
• -f == force
• --volumes == prune volumes.

see: https://docs.docker.com/engine/reference/commandline/system_prune/#description

as a side note, I had a lot of issues when I used devicemapper driver on my environment. I used to clean as I mentioned, but there were still other devicemapper issues. I strongly recommend moving to overlay2, it solved almost everything completely.

Answered By - Tidhar Klein Orbach

Answer Checked By - Mary Flores (WPSolving Volunteer)