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

Sun Mar 24 03:41:37 UTC 2013
Banyan He <banyan at rootong.com>

what do you find in dmesg and /var/log/messages? The system should bring 
it up automatically. If not, you should get an error for the prompts.

------------
Banyan He
Blog: http://www.rootong.com
Email: banyan at rootong.com

On 3/24/2013 10:27 AM, Joakim Ziegler wrote:
> I have a recently installed Mellanox VPI interface in my server. This is
> an InfiniBand interface, which, through the use of adapters, can also do
> 10GbE over fiber. I have one of the adapter's two ports configured for
> 10GbE in this way, with a point to point link to a Mac workstation with
> a Myricom 10GbE card.
>
> I've configured this interface on the Linux box (eth2) using
> /etc/sysconfig/network-scripts/ifcfg-eth2 , setting its IP address, MTU,
> subnet, etc.
>
> Everything seems to work fine, with a single exception. If I reboot the
> Mac on the other end, causing the link state of the fiber interface to
> bounce, the network interface on the Linux box doesn't come back up when
> the link comes back up. That is, ifconfig shows it as having the link
> up, but it doesn't do the equivalent of "ifup eth2" when the link comes
> back, so it doesn't get an IP, the routing table doesn't get updated, etc.
>
> So, my question is, how can I make CentOS automatically configure this
> interface when the link comes back up? It's a bit annoying having to log
> in and do ifup eth2 every time...
>