Re: [cobalt-users] Why do cobalts have two ethernets anyhow?

[Pitr <pitr@xxxxxxxxx>]

On Fri, 2003-06-06 at 16:25, Josh Kuperman wrote:
> I am curious why (some, eg.xtr, 550) cobalts have two ethernet
> interfaces. You can alias many ips to a single interface, which is how
> virtually hosted sites do it.

We configure almost all datacenter machines with dual nics.  One has
public/routable IP with restricted access (generally only ports WWW, FTP
and maybe SSH open).  Second IP has unroutable "private" IP with all
ports open, but no direct internet access.  In this way for example you
can shut down the public port, like if there is some weird worm or
problem or whatever and still access private IP port to do cleanup or
admin task.

Yes, this could all technically be done off of a single port, but it is
easier to keep the public and private LANs physically separate.

You could also have the 2 ports plugged into 2 different routers that
offer different traffic shaping patterns, ie: a limited throughput port,
and a wide-open port.