[c-nsp] VASI interface and NAT on ASR1k

[Matthew Melbourne]

Hi,

Does anyone have any pointers to some real-world use cases for VASI
interfaces on an ASR1k? I have a corner case where I can't use MP-BGP to
import a route from one VRF into another, when the next-hop of the route is
in a separate VRF (the case is VRF-aware IPsec with FVRF/iVRF
configuration). It looks like the issue can be worked around using VASI
interfaces (i.e. a vasileft/vasiright pair). I have used a /30 to address
the VASI interfaces and this appears to work, but is this best practice? NAT
may be another useful requirement in this scenario, but I have seen other
cisco-nsp postings which suggests 'ip nat outside' shouldn't be configured
on an interface which isn't in the global table. A suggestions is that "ip
nat enable" and hence NVI be used in preference to classic NAT for VASI
interfaces? VASI does appear to be a rather poorly documented feature in
IOS-XE :)

Cheers,
 
Matt
 
-- 
Matthew Melbourne