[K12OSN] eth alias help

[Les Mikesell]

On Thu, 2004-02-26 at 13:55, Steve Wright wrote:
> > Ok....Right now in my mail server I have 2 separate 10/100 nics recieving mail
> > for 2 separate domains. If I take those out and put one gig nic in...can I
> > create an alias (like eth 0:1) for the other domain and have things work like
> > normal from the same nic? I assume I can but want to make sure.
> 
> 
> Yes, you can, but it is the old way to do it.

But RedHat/Fedora systems have a handy GUI tool for interfaces
and aliases in redhat-config-network, and if you use it
the ifup/ifdown wrappers work and you can set it up to
automatically start at bootup.

> Simply add both addresses to the interface.  The interface will
> establish itself as usual, and then add the secondary IP address
> directly, thusly ;
> 
> 
> # ip address add 192.168.n.254/24 dev eth0

The one thing I have sometimes had trouble with is that
with multiple addresses on the same subnet the 'wrong'
one may be used as the source address on outbound
connections.  Is there a way to control that?

---
  Les Mikesell
   les at futuresource.com