VMMs and networks

[Bill Bogstad]

2009/4/1 Jerry Feldman <gaf-mNDKBlG2WHs at public.gmane.org>:
>....
>
> example:
> eth0 - host os ip address aaa.bbb.ccc.ddd - not used by VM
> eth1 - host os (no IP configured) - VM connected as aaa.bbb.ccc.dde

If you see this as two separate problems, it doesn't seem that hard to me.

1. Get host OS to not use eth1.  - This has nothing to do with VMs and
is totally host OS dependent. On modern Linux systems, Network Manager
has a tendency to bring up any interface which isn't statically
configured somewhere so you need to 'statically' configure etj1.
OTOH, you don't actually want the host OS to use eth1, but you do want
the interface brought
'up' so the VM can use it.  On Ubuntu, something like:

 auto eth1
 iface eth1 inet manual
      up ifconfig $IFACE 0.0.0.0 up
      down ifconfig $IFACE down

in the /etc/network/interfaces file will probably work.  The ifconfig
with no IP address should bring up the interface without making it
active for IP use by the host OS. It's been a while since I did
Fedora/Redhat, but I'm guessing something could be
put in /etc/sysconfig/network-scripts/ifcfg-eth1 to do something similar.

2. Get the VM to bridge to the eth1 interface. - Use whatever method
you would normally use to get the VM to use
eth1.  The VM shouldn't care that the host OS isn't using the interface.

Good Luck,
Bill Bogstad