Docker service does not start

Question

docker is gigving me a hard time currently. I followed these instructions in order to install docker on my virtual server running Ubuntu 14.04 hosted by strato.de.

wget -qO- https://get.docker.com/ | sh

Executing this line runs me directly into this error message:

modprobe: ERROR: ../libkmod/libkmod.c:507 kmod_lookup_alias_from_builtin_file() could not open builtin file '/lib/modules/3.13.0-042stab092.3/modules.builtin.bin'modprobe: FATAL: Module aufs not found.
Warning: current kernel is not supported by the linux-image-extra-virtual
 package.  We have no AUFS support.  Consider installing the packages  linux-image-virtual kernel and linux-image-extra-virtual for AUFS support.

After the installation was done, I installed the two mentioned packages. Now my problem is that I can't get docker to run.

service docker start

results in:

start: Job failed to start


docker -d

results in

INFO[0000] +job serveapi(unix:///var/run/docker.sock)
INFO[0000] Listening for HTTP on unix (/var/run/docker.sock)
ERRO[0000] 'overlay' not found as a supported filesystem on this host. Please ensure kernel is new enough and has overlay support loaded.
INFO[0000] +job init_networkdriver()
WARN[0000] Running modprobe bridge nf_nat failed with message: , error: exit status 1
package not installed
INFO[0000] -job init_networkdriver() = ERR (1)
FATA[0000] Shutting down daemon due to errors: package not installed

and

docker run hello-world

results in

FATA[0000] Post http:///var/run/docker.sock/v1.18/containers/create: dial unix /var/run/docker.sock: no such file or directory. Are you trying to connect to a TLS-enabled daemon without TLS?

Does anybody have a clue about what dependencies could be missing? What else could have gone wrong? Are there any logs which docker provides?

I'm searching back and forth for a solution, but couldn't find one.

Just to mention this is a fresh Ubuntu 14.04 setup. I didn't install any other services except for java. And the reason why I need docker is for using the dockerimage of sharelatex.

I'm thankful for any help!

Answer 1

Here's what I tried/found out, hoping that it will save you some time or even help you solve it.

Docker's download script is trying to identify the kernel through uname -r to be able to install the right kernel extras for your host.

I suspect two problems:

• My (united-hoster.de) and probably your provider use customized kernel images (eg. 3.13.0-042stab108.2) for virtual hosts. Since the script is explicitly looking for -generic in the name, the lookup fails.
• While the naming problem would be easy to fix, I wasn't able to install the generic kernel extras with my hoster's custom kernel. It seems like using a upgrading the kernel does not work either, since it would affect all users/vHosts on the same physical machine. This is because the kernel is shared (stated in some support ticket).

To get around that ..

• I skipped it, hoping that Docker would work without AUFS support, but it didn't.
• I tried to force Docker to use devicemapper instead, but to no avail.

I see two options: get a dedicated host so you can mess with kernels and filesystems or a least let the docker installer do it or install the binaries manually.