Docker push fails without detailed error message

General Discussions
1

I am new to docker and having trouble with docker push.
If I change anything on the published image after pulling it from a repository, I fail pushing it back.
But, If I pull an image and do nothing(no commit), I can push it back.

The following is what I have done. Does anyone have any clue?
At the end, you can find the information about docker and os version. Also I am behind a proxy.

base@ubuntu:~$ sudo docker pull ubuntu
base@ubuntu:~$ sudo docker run -t -i ubuntu /bin/bash
root@9b960ae783b0:/# echo hello > hello.txt
root@9b960ae783b0:/# exit
exit
base@ubuntu:~$ sudo docker commit 9b960ae783b0 yhong/test
4f0f7e3d5980200c0712ed9a33f129721bda8ce89bc0c39a3fda0510ce8bc144
basespace@ubuntu:~$ sudo docker push yhong/test
The push refers to a repository [yhong/test] (len: 1)
Sending image list
Pushing repository yhong/test (1 tags)
d3a1f33e8a5a: Image already pushed, skipping
c22013c84729: Image already pushed, skipping
d74508fb6632: Image already pushed, skipping
91e54dfb1179: Image already pushed, skipping
4f0f7e3d5980: Pushing [==================================================>] 3.584 kB/3.584 kB
FATA[0009]
base@ubuntu:~$ sudo docker version
Client version: 1.5.0
Client API version: 1.17
Go version (client): go1.4.1
Git commit (client): a8a31ef
OS/Arch (client): linux/amd64
Server version: 1.5.0
Server API version: 1.17
Go version (server): go1.4.1
Git commit (server): a8a31ef
base@ubuntu:~$ uname -a
Linux ubuntu 4.1.0-040100rc2-generic #201505032335 SMP Mon May 4 03:36:35 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux

2

The first thing I would recommend checking would be the docker daemon logs (usually the /var/log/docker.log file).

If there is nothing there, try restarting your daemon in debug mode --debug=true, and see if it reveals any more information about the error.

Also, since you are behind a proxy, checking the proxy’s access logs might reveal some information (if you have access to them)

/Jeff