Docker loading local images permission denied while processing tar file

Question

I have access to a server by ssh with docker version 1.13.1 and I'm just trying to load a local image using docker load -i and I'm receiving this error message:

docker load -i docker.img 
Error processing tar file(exit status 1): permission denied

And by the way:

docker image import docker.img
Error response from daemon: ApplyLayer exit status 1 stdout:  stderr: permission denied

The img file has all the permissions:

> ls -l
> -rwxrwxrwx  1 myuser myuser 9278464 Mar 22 19:12 docker.img*

And docker seems to work rigth:

> docker images
> REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE

The image works perfectly fine in my local machine...

Any idea about what can be happening here ? The host is running ubuntu 16.04, i was looking for an answer about 1 hour...

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Answer 1

You are trying to execute docker commands as which user?, Standard account or as root user?

Note that the docker daemon binds to a Unix socket instead of a TCP port. By default that Unix socket is owned by the user root and other users can only access it using sudo. The docker daemon always runs as the root user.

If you don’t want to use sudo when you use the docker command, create a Unix group called docker and add users to it. When the docker daemon starts, it makes the ownership of the Unix socket read/writable by the docker group.

First, check if docker group exists on your server. If not, then add it

$ sudo groupadd docker

Add your user to the docker group.

$ sudo usermod -aG docker $USER

Log out and log back in so that your group membership is re-evaluated

Answer 2

I could figure it out, the problem was that I was accessing a proxmox container not fully virtualized, so, docker requires kernel capabilities that I had not. I searched for the correct proxmox configuration and I solve the issue.