Old images filling the disk

[caspear]

Uptime Kuma does not seem to be cleaning up old docker images, which is slowly but surely filling the disk.

# docker images -q cloudron/louislam.uptimekuma.app | wc -l
56

# docker images cloudron/louislam.uptimekuma.app --format 'table {{.Tag}}\t{{.CreatedSince}}\t{{.Size}}'
TAG                  CREATED         SIZE
202611011424070000   4 days ago      2.49GB
202610311425350000   5 days ago      2.49GB
202610281425490000   8 days ago      2.49GB
202610231334320000   13 days ago     2.49GB
202610221334590000   2 weeks ago     2.49GB
202610201324590000   2 weeks ago     2.49GB
202610101326010000   3 weeks ago     2.48GB
202610061328140000   4 weeks ago     2.48GB
202609251853530000   5 weeks ago     2.48GB
202609230702240000   6 weeks ago     2.48GB
202609221324260000   6 weeks ago     2.58GB
202609121323500000   7 weeks ago     3.64GB
202609101324360000   8 weeks ago     3.64GB
202608311323360000   2 months ago    3.64GB
202608221323290000   2 months ago    3.64GB
202608151323590000   2 months ago    3.64GB
202608031037220000   3 months ago    3.65GB
202607231323390000   3 months ago    3.64GB
202607161323260000   3 months ago    3.63GB
202607101323560000   3 months ago    3.63GB
202606191323050000   4 months ago    3.63GB
202606091323070000   4 months ago    3.64GB
202605311323040000   5 months ago    3.64GB
202605251323070000   5 months ago    3.64GB
202605131324090000   5 months ago    3.64GB
202605040734180000   6 months ago    3.64GB
202605011457400000   6 months ago    3.64GB
202603100309490000   8 months ago    3.62GB
202603050653400000   8 months ago    3.58GB
202602191408550000   8 months ago    3.61GB
202602131712530000   8 months ago    3.6GB
202602090716130000   9 months ago    3.64GB
202602071425440000   9 months ago    3.75GB
202601271425310000   9 months ago    3.75GB
202601201425020000   9 months ago    3.74GB
202511081423470000   12 months ago   3.74GB
202511071426450000   12 months ago   3.74GB
202510311426170000   12 months ago   3.74GB
202510211435340000   12 months ago   3.74GB
202509231325220000   13 months ago   4.32GB
202509181325050000   13 months ago   4.32GB
202508221422060000   14 months ago   4.32GB
202508091326260000   15 months ago   4.33GB
202507041324150000   16 months ago   4.33GB
202506171327000000   16 months ago   4.33GB
202506111326470000   17 months ago   4.32GB
202505161324190000   17 months ago   4.32GB
202505011323380000   18 months ago   4.31GB
202504071849220000   19 months ago   4.31GB
202504031324250000   19 months ago   3.69GB
202503271803390000   19 months ago   3.69GB
202502271429150000   20 months ago   3.36GB
202502051425410000   21 months ago   3.36GB
202501311424270000   21 months ago   3.36GB
202501071425390000   22 months ago   3.36GB
202412200803170000   22 months ago   3.34GB

# docker system df
TYPE            TOTAL     ACTIVE    SIZE      RECLAIMABLE
Images          90        30        120.2GB   75.35GB (62%)
Containers      98        64        0B        0B
Local Volumes   173       173       12.55GB   0B (0%)
Build Cache     0         0         0B        0B

[james]

Hello @caspear
What Cloudron version is your server running?

[caspear]

# echo "Cloudron $(cat /home/yellowtent/box/VERSION)"
Cloudron 10.1.6

[james]

Hello @caspear
Please run the following commands and send me the output from your server:

docker ps -a --format '{{.ID}} {{.Image}} {{.Names}} {{.Status}} {{.Label "appId"}} {{.Label "isCloudronManaged"}}' | grep -i uptimekuma
docker images --digests | grep -i uptimekuma | head
grep -h "deleteImage: removing cloudron/louislam" /home/yellowtent/platformdata/logs/tasks/*.log | tail

[caspear]

# docker ps -a --format '{{.ID}} {{.Image}} {{.Names}} {{.Status}} {{.Label "appId"}} {{.Label "isCloudronManaged"}}' | grep -i uptimekuma
docker images --digests | grep -i uptimekuma | head
grep -h "deleteImage: removing cloudron/louislam" /home/yellowtent/platformdata/logs/tasks/*.log | tail
167109c4b757 cloudron/louislam.uptimekuma.app:202611011424070000 95a0b41d-0525-4b60-b62e-3bb8b11edaf2 Up 2 days 95a0b41d-0525-4b60-b62e-3bb8b11edaf2 true
cloudron/louislam.uptimekuma.app               202611011424070000          <none>                                                                    81ce16f02a7e   4 days ago      2.49GB
cloudron/louislam.uptimekuma.app               202610311425350000          sha256:585554c282e88cfa79efd6f6ef0e651700f394de3d2e5f7ae8f48bb612b160d8   555d251b4542   5 days ago      2.49GB
cloudron/louislam.uptimekuma.app               202610281425490000          sha256:15ade59f35a8aa256706bb8c7930b9a6a56270c2d2b3bb6b39d472c0100ac464   a8fee11920ee   8 days ago      2.49GB
cloudron/louislam.uptimekuma.app               202610231334320000          sha256:0c00116c5fb25f8c58ebd40505b849c26d0252220883403586d3ec64cc1ccdf7   5db34eb4f263   13 days ago     2.49GB
cloudron/louislam.uptimekuma.app               202610221334590000          sha256:7da13fbe7c4a0e14f0de5f000ffc773b68a573de349c5fd318deba7a79098c06   a8885b2c1967   2 weeks ago     2.49GB
cloudron/louislam.uptimekuma.app               202610201324590000          sha256:1f02d509787ccea7f2e016dc75ae5a32d36a2c0d8a394ad21d3b1fed943e0861   1fc29da1e576   2 weeks ago     2.49GB
cloudron/louislam.uptimekuma.app               202610101326010000          sha256:4b3938f95fa9b0dd525feacae43b8f9c2471e855177e0bcc8aebf41acf8be1c2   0ed29fbb1a3e   3 weeks ago     2.48GB
cloudron/louislam.uptimekuma.app               202610061328140000          sha256:47bdd8aa81cd64880741735676c6abac34835c142f96c0182c86fdb4895646a4   41ee44f20c5b   4 weeks ago     2.48GB
cloudron/louislam.uptimekuma.app               202609251853530000          sha256:d00039a73a9b8e6e88c1ad9040ba99a4f5f8998970538c0813c35171596b9f81   b784b501be0e   5 weeks ago     2.48GB
cloudron/louislam.uptimekuma.app               202609230702240000          sha256:91938385453ce51292f868822ccda85d4d562429a9da7b8099b1de31e8681d27   9c9a62d0439a   6 weeks ago     2.48GB

[james]

Hello @caspear
It looks like you did not correctly execute the commands or did some of them really return nothing?
There is a # at the start of the first command which would make it a comment in bash and execute nothing.

[caspear]

I pasted them together and so they executed sequentially. The # at the beginning is the root prompt.

I will execute them again one at a time so that it is more clear.

# docker ps -a --format '{{.ID}} {{.Image}} {{.Names}} {{.Status}} {{.Label "appId"}} {{.Label "isCloudronManaged"}}' | grep -i uptimekuma
167109c4b757 cloudron/louislam.uptimekuma.app:202611011424070000 95a0b41d-0525-4b60-b62e-3bb8b11edaf2 Up 2 days 95a0b41d-0525-4b60-b62e-3bb8b11edaf2 true

# docker images --digests | grep -i uptimekuma | head
cloudron/louislam.uptimekuma.app               202611011424070000          <none>                                                                    81ce16f02a7e   5 days ago      2.49GB
cloudron/louislam.uptimekuma.app               202610311425350000          sha256:585554c282e88cfa79efd6f6ef0e651700f394de3d2e5f7ae8f48bb612b160d8   555d251b4542   5 days ago      2.49GB
cloudron/louislam.uptimekuma.app               202610281425490000          sha256:15ade59f35a8aa256706bb8c7930b9a6a56270c2d2b3bb6b39d472c0100ac464   a8fee11920ee   8 days ago      2.49GB
cloudron/louislam.uptimekuma.app               202610231334320000          sha256:0c00116c5fb25f8c58ebd40505b849c26d0252220883403586d3ec64cc1ccdf7   5db34eb4f263   2 weeks ago     2.49GB
cloudron/louislam.uptimekuma.app               202610221334590000          sha256:7da13fbe7c4a0e14f0de5f000ffc773b68a573de349c5fd318deba7a79098c06   a8885b2c1967   2 weeks ago     2.49GB
cloudron/louislam.uptimekuma.app               202610201324590000          sha256:1f02d509787ccea7f2e016dc75ae5a32d36a2c0d8a394ad21d3b1fed943e0861   1fc29da1e576   2 weeks ago     2.49GB
cloudron/louislam.uptimekuma.app               202610101326010000          sha256:4b3938f95fa9b0dd525feacae43b8f9c2471e855177e0bcc8aebf41acf8be1c2   0ed29fbb1a3e   3 weeks ago     2.48GB
cloudron/louislam.uptimekuma.app               202610061328140000          sha256:47bdd8aa81cd64880741735676c6abac34835c142f96c0182c86fdb4895646a4   41ee44f20c5b   4 weeks ago     2.48GB
cloudron/louislam.uptimekuma.app               202609251853530000          sha256:d00039a73a9b8e6e88c1ad9040ba99a4f5f8998970538c0813c35171596b9f81   b784b501be0e   5 weeks ago     2.48GB
cloudron/louislam.uptimekuma.app               202609230702240000          sha256:91938385453ce51292f868822ccda85d4d562429a9da7b8099b1de31e8681d27   9c9a62d0439a   6 weeks ago     2.48GB

# grep -h "deleteImage: removing cloudron/louislam" /home/yellowtent/platformdata/logs/tasks/*.log | tail

Last command returns nothing - uptime kuma images never get deleted, that is indeed my bug report!

[james]

Hello @caspear

Thanks for the output. It rules out a leftover container holding the old images: only the current Kuma container exists.

Your current image has no digest (<none>), but every old image has a sha256: digest. Cloudron downloads app images under a registry name and then retags them, and an image downloaded that way has no digest.
It looks like your old images are being pulled a second time after an app update has deleted them.

My suspicion is a race between the nightly full backup and the app auto-update. By default both start at 23:00.

Please run these two commands:

docker image inspect --format '{{index .RepoTags 0}} {{.Metadata.LastTagTime}}' cloudron/louislam.uptimekuma.app:202610311425350000 cloudron/louislam.uptimekuma.app:202611011424070000

grep -H "uptimekuma.app:202610311425350000" /home/yellowtent/platformdata/logs/tasks/*.log /home/yellowtent/platformdata/logs/95a0b41d-0525-4b60-b62e-3bb8b11edaf2/apptask.log* | cut -c1-300

If the first command shows a time after the update on 1 November for the older tag, or a backup task log mentions the old tag after the update, that could confirm the race.

Until there is a fix, you can safely remove the old images with docker rmi <image>:<tag> for every tag except the one in use.

[james]

Hello @caspear

You might have found a "good" issue there.
Thanks for reporting! We are investigating this more detailed.

[caspear]

@james said:

grep -H "uptimekuma.app:202610311425350000" /home/yellowtent/platformdata/logs/tasks/.log /home/yellowtent/platformdata/logs/95a0b41d-0525-4b60-b62e-3bb8b11edaf2/apptask.log | cut -c1-300

# docker image inspect --format '{{index .RepoTags 0}} {{.Metadata.LastTagTime}}' cloudron/louislam.uptimekuma.app:202610311425350000 cloudron/louislam.uptimekuma.app:202611011424070000
cloudron/louislam.uptimekuma.app:202610311425350000 0001-01-01 00:00:00 +0000 UTC
cloudron/louislam.uptimekuma.app:202611011424070000 2026-11-01 23:00:41.030181353 +0000 UTC

# grep -H "uptimekuma.app:202610311425350000" /home/yellowtent/platformdata/logs/tasks/*.log /home/yellowtent/platformdata/logs/95a0b41d-0525-4b60-b62e-3bb8b11edaf2/apptask.log* | cut -c1-300
/home/yellowtent/platformdata/logs/tasks/12500.log:2026-11-01T23:32:35.295Z shell: services: /bin/bash -c docker run --rm --name=sqlite-95a0b41d-0525-4b60-b62e-3bb8b11edaf2             --net cloudron             --log-driver=none             -v /home/yellowtent/appsdata/95a0b41d-0525-4b60-b62e-3bb8b
/home/yellowtent/platformdata/logs/tasks/12500.log:2026-11-01T23:33:02.040Z shell: services: /bin/bash -c docker run --rm --name=sqlite-95a0b41d-0525-4b60-b62e-3bb8b11edaf2             --net cloudron             --log-driver=none             -v /home/yellowtent/appsdata/95a0b41d-0525-4b60-b62e-3bb8b
/home/yellowtent/platformdata/logs/95a0b41d-0525-4b60-b62e-3bb8b11edaf2/apptask.log:2026-11-01T01:00:12.842Z docker: downloadImage: cloudron/louislam.uptimekuma.app:202610311425350000
/home/yellowtent/platformdata/logs/95a0b41d-0525-4b60-b62e-3bb8b11edaf2/apptask.log:2026-11-01T01:00:12.847Z docker: pullImage: will pull registry.docker.com/cloudron/louislam.uptimekuma.app:202610311425350000. auth: no
/home/yellowtent/platformdata/logs/95a0b41d-0525-4b60-b62e-3bb8b11edaf2/apptask.log:2026-11-01T01:00:36.738Z docker: pullImage: {"status":"Status: Downloaded newer image for registry.docker.com/cloudron/louislam.uptimekuma.app:202610311425350000"}
/home/yellowtent/platformdata/logs/95a0b41d-0525-4b60-b62e-3bb8b11edaf2/apptask.log:2026-11-01T01:00:36.741Z docker: downloaded image registry.docker.com/cloudron/louislam.uptimekuma.app:202610311425350000 . error: false
/home/yellowtent/platformdata/logs/95a0b41d-0525-4b60-b62e-3bb8b11edaf2/apptask.log:2026-11-01T01:00:36.741Z docker: downloadImage: tagging registry.docker.com/cloudron/louislam.uptimekuma.app:202610311425350000 as cloudron/louislam.uptimekuma.app:202610311425350000
/home/yellowtent/platformdata/logs/95a0b41d-0525-4b60-b62e-3bb8b11edaf2/apptask.log:2026-11-01T01:00:36.748Z docker: downloadImage: untagging registry.docker.com/cloudron/louislam.uptimekuma.app:202610311425350000
/home/yellowtent/platformdata/logs/95a0b41d-0525-4b60-b62e-3bb8b11edaf2/apptask.log:2026-11-01T01:00:36.748Z docker: deleteImage: removing registry.docker.com/cloudron/louislam.uptimekuma.app:202610311425350000
/home/yellowtent/platformdata/logs/95a0b41d-0525-4b60-b62e-3bb8b11edaf2/apptask.log:2026-11-01T23:00:02.520Z shell: services: /bin/bash -c docker run --rm --name=sqlite-95a0b41d-0525-4b60-b62e-3bb8b11edaf2             --net cloudron             --log-driver=none             -v /home/yellowtent/appsd
/home/yellowtent/platformdata/logs/95a0b41d-0525-4b60-b62e-3bb8b11edaf2/apptask.log:2026-11-01T23:00:06.820Z shell: services: /bin/bash -c docker run --rm --name=sqlite-95a0b41d-0525-4b60-b62e-3bb8b11edaf2             --net cloudron             --log-driver=none             -v /home/yellowtent/appsd
/home/yellowtent/platformdata/logs/95a0b41d-0525-4b60-b62e-3bb8b11edaf2/apptask.log:2026-11-01T23:00:42.444Z docker: deleteImage: removing cloudron/louislam.uptimekuma.app:202610311425350000

[caspear]

Oh no!

To me this does not immediately feel like a race condition: These images are very reliably retained, and other types of images get cleaned up without any issues. So, why this one?

I am happy to add a cron job that deletes all but the 3-4 most recent ones, just to see if the issue is still recurring.

[james]

Hello @caspear
We already have narrowed it down to a race condition happening when the SQLite addon is used.
Uptimekuma uses the SQLite addon.

[caspear]

Fantastic!