[Xorp-users] Xorp, pimsm and ethertap

[Pavlin Radoslavov]

> On Thu, Feb 23, 2006 at 11:47:34AM +0000, Calum wrote:
> > 1. Does xorp handle tap/tun interfaces created by other processes
> > before xorp runs in just the same way as it handles "standard"
> > Ethernet interfaces?
> 
> Yes.
> 
> > 2. Is there anything special you have to enable to use it that way?
> 
> No.
> 
> > 3. Why am I getting this? : Cannot enable vif tapxxxx: no such vif (As
> > I say, I have literally compiled this a few minutes ago, so I'll
> > probably work it out as soon as I hit send. (However, if xorp doesn't
> > play with tap/tun, please let me know and save me hair-pulling hours!)
> > :)
> 
> You must have a 'vif tunxxxx {}' statement in the interface configuration.

Some additional information on the subject.

To be able to use a tun/tap interface (or any network interface in
general), it must be already created before starting XORP (though it
doesn't need to be configured with IP address, etc).

If you have the tun/tap interface already configured with an IP
address you want to (re)use, then you can use the following
statement in your configuration:

interfaces {
    interface tun0 {
        default-system-config
    }
}

If the IP address is not configured or if you want to explicitly
configure the address in your XORP configuration, then use a
statement like:

interfaces {
    interface tun0 {
        vif tun0 {
            address 10.10.10.10 {
                prefix-length: 24
            }
        }
    }
}

See the XORP user documentation for more information about
configuring network interfaces and for examples of configuring
multicast routing.

If you are still getting the above error, then please send your
XORP configuration and the list of UNIX commands (if such) you used
to configure the tap interface.

Pavlin