Feature Request: add "machine_hostname" metric

[liseri]

Problem: run cadvisor with docker model(dns config in prometheus), cann't found the real ip of the host machine, only found the docker ip.

Solution: Use the docker hostname is one solution, but , cadvisor have not hostname metric like "node_uname_info" in node_exporter. So, I want to add a new metric named "machine_hostname", like this:

Usage: like this:

[liseri]

I add a PR #3220

[roadSurfer]

Thanks for this. Not being able to tie a CAdvisor instance back to the specific host is a major frustration. Hopefully it gets merged soon.

[DerekChia]

This is something very useful, not sure why PR is still not merged

[MingNiu]

Any progress so far?