[CentOS] How to make a network interface come up automatically on link up?

Tue Apr 23 10:09:35 UTC 2013
Carl T. Miller <carl at carltm.com>

On 04/23/2013 05:25 AM, John Doe wrote:
> From: Joakim Ziegler <joakim at terminalmx.com>
>> As I'd mentioned before, the problem isn't that the interface doesn't
>> come up on boot, it does, but since it's a point to point interface,
>> when I reboot the computer on the other end, it goes down and doesn't
>> come back up automatically. That is, link going down and up makes the
>> network configuration stay down, I have to manually take the interface
>> down and back up to make it work again.
> Not the solution you want but, as a last resort, you could always have a
> cron script that checks every minute if the link is down...

Or consider putting "* * * * * /sbin/ifup eth2" in root's crontab.  If
eth2 is up, it simply rereads the configs (which haven't changed).  If
it was down, it brings it up.