Docker push is getting stuck at pushing one layer

Docker Desktop
1

I encountered a problem when trying to push an image to a local registry. Everything builds OK, I can start the container, but I am unable to push it successfully to the registry. The push will run for several hours, consuming as much memory as it can (~16-17 GB is where it usually ends up), and then it quits. The process com.docker.service won’t release the memory after this, so a restart is required.

The push itself starts as usual, but one layer is extremely slow and often drops down a hundred megs or so after a while. The output looks something like this:

e63182f8f000: Layer already exists
7451b27a9acf: Pushing [===========================================>]  74.24kB/74.24kB
c11ddffd11fc: Pushing [===========================================>]  86.53kB/86.53kB
8225699703ad: Pushing [===========================================>]  205.4MB/205.4MB
a004118b76dc: Pushing [===========>                                ]  154.1MB/563.3MB
92961e2db95b: Layer already exists
67044ff0aa8f: Layer already exists

I have managed to isolate the problem to this step in the Dockerfile:

FROM ubuntu:18.04
...
RUN apt-get update && \
    apt-get install -y azure-cli

Basically, the only thing the container contains is support for Azure-CLI and Kubernetes.

The same problem occurs on two different computers, both running Win10 1809. I have tried both Docker stable and 2.0.2.1 edge.

Any tips on how to solve the problem or how to further investigate what might be the cause?

1 Like
2

I get something similar trying to push an image with a 700MB layer.
It gets to 450MB and then bails with:
error creating overlay mount to /var/lib/docker/overlay2/f80d03a6c9335315dddb2c5e804f888317beb3a3913006478d55324b5343a5f9/merged: device or resource busy

3

I solved my problem setting

“max-concurrent-uploads”: 1

in /etc/docker/daemon.json, and restarting, pushing

1 Like
4

Have same problem.
Two different machines and same error.
I am pushing on hub.docker.com and also in registry.gitlab.com it freeze itself in one layer.
Can not find a solution. Tried to set max concurrent uploads to 1 and same thing.
Tried installing new and older versions and same thing.
Sometimes is going without any problem and sometimes it is just freezing.

1 Like
5

I used the following command and it solved the stuck pushing for me.

sudo systemctl restart docker
3 Likes
6

This worked. Thanks!

7

Very weird. My uploads were taking a long time and the large layers would timeout. After restarting the docker daemon the upload is much faster. There might be some bug in the daemon that requires an occasional restart.

1 Like