Re: [atomic-devel] Cockpit in Super Privileged Container for older EL6 servers

[Stef Walter <stefw redhat com>]

On 20.10.2015 02:48, Donald DAvanzo wrote:
> I am looking for a way to run docker on older Centos 6x installs in
> which the image is el7 and super privileged so that Cockpit on el6
> servers can be seen by our main cockpit install.
> 
> We have several hundred vms in our cloud that are el6x and will not be
> able migrated to el7x for some time.
> 
> Our vision is for the docker super privileged image running on the el6
> servers to have a el7 cockpit image only and to be used as read only for
> monitoring resources / storage and ssh access. Then from our main
> cockpit portal were we are adding all our servers we would tell it to
> connect to the cockpit el7 docker image running on the el6 servers.
> 
> Anyone have any thoughts on this or the direction we should go? 

Cockpit can be thought of as two parts: The frontend in the browser, and
the backend bridge/transport.

The bridge exists as a way to expose the system's APIs to the frontend
running in your browser:

http://stef.thewalter.net/protocol-for-web-access-to-system-apis.html

Currently there are Cockpit frontend components for things like systemd
and NetworkManager. Cockpit talks directly to these system service APIs.
You can see a full list here:

http://files.cockpit-project.org/guide/latest/features.html

There are currently no frontends for RHEL 6 "APIs", such as sysvinit or
/etc/sysconfig/network. In theory someone could write such Cockpit
frontend UI for RHEL 6, I'm not ruling that out, but it would not be
easy and certainly doesn't exist today.

A good example is RHEL 7's use of systemd. It exposes concrete tractable
APIs for system management, time and date, NTP, locale, hostname,
cgroups (eg: metrics), login sessions, journal, shutdown/reboot ... and
so on. It is ontop of these APIs that the Cockpit interactive UI has
been written.

So the upshot is, even if you did get Cockpit working as described ...
off the top of my head only the following parts would be useful on RHEL 6:

 * Docker (for as long as its continues to work on RHEL 6)
 * Local user accounts
 * Terminal

In addition, if you can get storaged working in a container, on a RHEL 6
kernel, with mismatched LVM tools ... then perhaps that might work to:

https://github.com/storaged-project/storaged/

So with these caveats, if you do want to contribute to make this base
level of functionality work as you describe, feel free to join us at
#cockpit on FreeNode or at:

https://github.com/cockpit-project/cockpit

Stef