docker-registry disk full and no ideas to diet it - docker

Question

I have a server with a docker registry, and have pushed a lot of times a build the same :latest tag now my DD is full and I can't get how to diet it.
disk is full
df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 48G 45G 397M 100% /
udev 10M 0 10M 0% /dev
tmpfs 794M 81M 713M 11% /run
tmpfs 2.0G 0 2.0G 0% /dev/shm
tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs 2.0G 0 2.0G 0% /sys/fs/cgroup
/dev/dm-1 9.8G 56M 9.2G 1% /var/lib/docker/devicemapper/mnt/2e895760700ac3e1575e496a4ac6adde4de6129226febba8c0c3126af1655ad9
shm 64M 0 64M 0% /var/lib/docker/containers/5aa47e34d1b8be22deeae473729b4e587e6e4bfe7fb3e262eda891bad4b05042/shm
there is no dangling volume nor images
# docker volume ls -qf dangling=true
#
# docker images -f "dangling=true" -q
#
docker images
[root#kvm22:/etc/cron.daily] # docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
jwilder/nginx-proxy 0.5.0 72b65b5a6f38 4 weeks ago 248.4 MB
registry 2 c9bd19d022f6 11 weeks ago 33.27 MB
registry 2.5 c9bd19d022f6 11 weeks ago 33.27 MB
disk usage
# du -h -d 7 /var/lib/docker/volumes/
12K /var/lib/docker/volumes/24000fbe2e81da06924be8f7ce81e07101824036bca5f87d4d811f2a6f7bfa7b/_data
16K /var/lib/docker/volumes/24000fbe2e81da06924be8f7ce81e07101824036bca5f87d4d811f2a6f7bfa7b
42G /var/lib/docker/volumes/registry_docker-registry-volume/_data/docker/registry/v2/blobs/sha256
42G /var/lib/docker/volumes/registry_docker-registry-volume/_data/docker/registry/v2/blobs
5.9M /var/lib/docker/volumes/registry_docker-registry-volume/_data/docker/registry/v2/repositories/labor-prod
5.9M /var/lib/docker/volumes/registry_docker-registry-volume/_data/docker/registry/v2/repositories
43G /var/lib/docker/volumes/registry_docker-registry-volume/_data/docker/registry/v2
43G /var/lib/docker/volumes/registry_docker-registry-volume/_data/docker/registry
43G /var/lib/docker/volumes/registry_docker-registry-volume/_data/docker
43G /var/lib/docker/volumes/registry_docker-registry-volume/_data
43G /var/lib/docker/volumes/registry_docker-registry-volume
43G /var/lib/docker/volumes/
Output of docker version:
# docker --version
Docker version 1.12.4, build 1564f02
Output of docker info:
# docker info
Containers: 4
Running: 1
Paused: 0
Stopped: 3
Images: 5
Server Version: 1.12.4
Storage Driver: devicemapper
Pool Name: docker-8:1-1184923-pool
Pool Blocksize: 65.54 kB
Base Device Size: 10.74 GB
Backing Filesystem: ext4
Data file: /dev/loop0
Metadata file: /dev/loop1
Data Space Used: 1.058 GB
Data Space Total: 107.4 GB
Data Space Available: 3.036 GB
Metadata Space Used: 2.142 MB
Metadata Space Total: 2.147 GB
Metadata Space Available: 2.145 GB
Thin Pool Minimum Free Space: 10.74 GB
Udev Sync Supported: true
Deferred Removal Enabled: false
Deferred Deletion Enabled: false
Deferred Deleted Device Count: 0
Data loop file: /var/lib/docker/devicemapper/devicemapper/data
WARNING: Usage of loopback devices is strongly discouraged for production use. Use `--storage-opt dm.thinpooldev` to specify a custom block storage device.
Metadata loop file: /var/lib/docker/devicemapper/devicemapper/metadata
Library Version: 1.02.90 (2014-09-01)
Logging Driver: json-file
Cgroup Driver: cgroupfs
Plugins:
Volume: local
Network: bridge null host overlay
Swarm: inactive
Runtimes: runc
Default Runtime: runc
Security Options:
Kernel Version: 3.16.0-4-amd64
Operating System: Debian GNU/Linux 8 (jessie)
OSType: linux
Architecture: x86_64
CPUs: 2
Total Memory: 3.873 GiB
Name: kvm22
ID: G6OC:EKKY:ER4W:3JVZ:25BI:FF2Y:YXVA:RZRR:WPAP:SASB:AJJA:DM6J
Docker Root Dir: /var/lib/docker
Debug Mode (client): false
Debug Mode (server): false
Registry: https://index.docker.io/v1/
WARNING: No memory limit support
WARNING: No swap limit support
WARNING: No kernel memory limit support
WARNING: No oom kill disable support
WARNING: No cpu cfs quota support
WARNING: No cpu cfs period support
Insecure Registries:
127.0.0.0/8

Answer 1

I had the same problem. I can't believe there's no ready solution for this. Anyway I hacked a tool together and it seems to work.
You can find it here: https://github.com/Richie765/docker-tools
Basically it uses a bash script to find out which manifests are untagged. Then deletes them through the registry API. Afterwards you can run a garbage collection to actually delete the data.
I'm sure the script isn't perfect. Any improvements are welcome!

Answer 2

Found another tool here.
https://github.com/burnettk/delete-docker-registry-image
Included a clean_old_version.py script.
I give it a try too.

Answer 3

In case anyone still has this problem:
This is the 'reset' way how I solved it:
You can stop and delete the registry
docker stop registry && docker rm -v registry
and restart it afterwards:
docker run -d -p 5000:5000 --restart=always --name registry registry:2
Then you would have to rebuild your images localy and push them to the registry again.