Forced routing

[Uncle Jim]

Hi,

On Tue, Nov 13, 2007 at 11:40:22PM -0600, Monty J. Harder wrote:

> If you want packets addressed to 229.255.0.1 to be sent via eth0, then try
> using this command:
> */sbin/route add -host 229.255.0.1 dev eth0*

I'm not a multicast expert (or even multicast user) BUT my guess is that the
proper command should be:

   /sbin/route add -net 224.0.0.0 netmask 240.0.0.0 dev eth0

This is not to say that Monty's command wouldn't work but that this is the
more general command for the 224.0.0.0/4 (224.0.0.0 - 239.255.255.255)
multicast network.

> Put it in /etc/rc.local so it will always be run at boot.

Monty has spent too much time in the SCO world.  On a RedHat system you should
use /etc/rc.d/rc.local.

> This should allow other multicast packets to stay on eth1.

I don't know why you would want other multicast packets to go to "The Internet"
rather than your local 10. network but your 169.254.0.0 traffic, which is
defined as "LINKLOCAL", is still not on your "local" network.  But since you
don't use it, who cares?

The other thing you need to verify is that the fourth line of the output of
"ifconfig eth0" includes the word "MULTICAST".  I'm sure it does, my CentOS
3.0 server has it by default.
-- 
Jim