Re: Where does NM persists which connection is active? (Centos7)

[Edward Haas <ehaas redhat com>]

On Sun, Sep 11, 2016 at 10:56 PM, Thomas Haller <thaller redhat com> wrote:

On Sun, 2016-09-11 at 15:45 +0300, Edward Haas wrote:
> Hello,
>
> Assuming there are multiple connection defined for an ethernet device
> and only a single one is active, how can I detect which ifcfg file
> was used for the connection?
>
> I cannot use nmcli for this, as NetworkManager is down at the moment
> I need the information.
> I just hope this info is available somewhere (as when starting NM,
> the correct connection is activated).
>
> Thanks,
> Edy.

Hi,


If NetworkManager is not running, there isn't a concept of "active
connection". What would that be?

NM is defining multiple connection/ifcfg files, I hoped to have the last active one

referenced somewhere.
The fact that NM leaves multiple ifcfg files with autoconnect enabled is a problem,
it is not a supported state for initscripts.

 

When NM starts and the device has IP configuration, NM will pick a
connection that matches to what is currently configured on the
interface. In my opinion, that is a wrong thing, but that is what
currently happens. https://bugzilla.gnome.org/show_bug.cgi?id=746440 is
supposed to improve on that, and it also will write a state-file that
contains which connection was active on a device when NetworkManager
stopped.

Is this considered for back-porting to centos7/rhel7?

When the device has no IP configuration at startup, NetworkManager will
autoconnect one of the available connections. Thereby it takes into
account connection.autoconnect-priority and connection.timestamp.


Maybe it would be helpful to explain what you are trying to do as an
end-goal. If NetworkManager is not running, why would you want to know
which connection was active when it stopped?
 

Thomas

It is related to an oVirt node that is initially setup using Cockpit (through NM).

Then, VDSM is installed and NM is disabled to avoid collisions.

At this point, VDSM is required to acquire the last active ifcfg file and adjust it

for VDSM.

The problem is: There may be multiple such ifcfg files, so which one should be

acquired and which should be just removed?

This is actually an intermediate solution, I would prefer to either leave NM running

and work with it, or ask it to 'ignore' devices.

ifcfg is also something we should stop using directly.

But all of these options won't happen in the immediate time frame, and we need

something now.

Thanks,

Edy.