[Xorp-users] Loopback address

[Bruce Simpson]

Luca Belforte wrote:
> I'm trying to set up a loopback address on my routers, used instead of
> the address of an interface, in case a link will not work.
> But i can't find how do it, i modified the lo address, but the address
> is not "forwarder" to other routers, so i can't ping it.
>
> in cisco we can do like this:
>
> interface Loopback0
> description "*** Loopback ***"
> no ip address
> ipv4 address 10.0.1.1/32
> ipv4 ospf area 0
> exit
>
>
> How i can set up the same in Xorp?
>   

I believe you'll need to configure the 'lo' interface manually within 
the XORP configuration.

The FEA has a certain amount of support for software interfaces; the 
'discard' interface, for example, is a purely software mechanism, which 
isn't implemented consistently across all forwarding platforms.

For the Linux case, you'll probably need to set up an IPv4 alias on lo 
in the interfaces {} block. For BSDs, the same may work, but you might 
wish to 'clone' a separate loX instance during system startup (something 
XORP can't do for you directly).

I can't think of any reason off the top of my head why it should not be 
possible to redistribute routes which reference that interface by 
address, unless the protocol(s) involved are trying to omit local 
addresses for whatever reason.

thanks,
BMS