Red Hat Enterprise Linux Atomic Host 7 Getting Started with Containers 


The problem occurred when was registering my machine for subscription.
subscription-manager register --username=rhnuser --password=rhnpasswd (RHEL)
subscription-manager register --username=rhnuser --password=rhnpasswd --auto-attach 

This did not work, but it worked if I typed the command only, forcing it to prompt for credentials.

I tried surrounding the credentials in single quotes, and then it worked fine.   The subscription-manager manpage does not specify using quotes, so this might be worth a mention in the docs.


Matching the installed system to a matching pool id was also a bit of a pain. I could not find the examples given (rhel-7-server-extras-rpms).   I ended up randomly registering for pools that seemed to match my installed base, only to have yum install docker fail because of repo mismatches.    However, I understand that given the long list of pools, it might be hard to specify how to derive a definitive pool match.

An ideal pseudoexample would be:

1. Don't do this from the console - you need to cut-paste a long UUID,  so SSH into the system or use a remote terminal that supports cut/paste.

2. Determine unique <string> from installed RHEL base.   [this is the missing step]

3. Do:  # subscription-manager list --available | grep <string>.

4. Copy the pool ID, such as bd3ab6f0b73911e680f576304dec7eb7.

5. Attach the pool:  # subscription-manager attach --pool=bd3ab6f0b73911e680f576304dec7eb7.

6. Enable the repos:  [name of required repos].

I could not find the specified repos  (--enable=rhel-7-server-extras-rpms, rhel-7-server-optional-rpms), I guess these have changed so I just did:

# subscription-manager repos --enable=rhel-7*

After that I was able to install and start docker.