Re: network manager always deconfigure the ethernet interface when network link is down

[Dan Williams <dcbw redhat com>]

On Mon, 2009-09-07 at 23:05 +0200, Luc Deschenaux wrote:
> Hi !
> 
> This behaviour is extremely annoying when you connect directly some
> machine with a crossover cable for netbooting (eg to install a system on
> a machine without cdrom player, to scan for viruses, backuping, resizing
> partitions, or whatever)
> 
> Or when ethernet interface is connected to a Powered Over Ethernet (POE)
> device directly through a POE power supply and that you need to reboot
> it.
> 
> The link is lost each time you connect the ethernet cable on another
> machine and each time you reboot the connected machine. And each time
> you need to activate the needed configuration again.
>  
> Trying to flash the firmware of a handfull of POE devices will quickly
> make you hate the network manager... especially if you have to
> reconfigure some routes manually also.
> 
> It would be nice to be able to declare an ethernet configuration as
> being "sticky" so that the interface would not deconfigure itself when
> the link is down, and not try to reconfigure itself automatically when
> the link is up again.

That's something I've discussed with various people, but before we do
that, we should add a few-second grace-period to the link instead of
just tearing it down immediately.  How long is the link actually down
before it comes back up?  I have also encountered this when doing
crossover stuff but it's always back up in a matter of seconds.

Dan