Due to a number of reasons we have a rather unique requirement to use IPv4+labels as a means to install a BGP next-hop against which other labelled BGP routes can be resolved. Though this sounds fairly complex I was hoping to acheive this as follows, (basic example):
R1 (loop0 = a, loop1 = b) <---- -----> R2 (loop0 = y, loop1 = z)
There is an IGP session between R1 and R2, whereby loop0 and the inter-link are inserted into the IGP, a BGP IPv4 + labels session is established between loop0's (a and y), over this session R1 advertises b --> R2, and R2 advertises z --> R1. Using route-maps, further labelled prefixes advertised between R1 and R2 have the BGP next-hop modified to b and z respectively.
Everything looks as I would expect, labels advertised / received as I would expect, (RIB entires etc), however, CEF shows recursion issues. I have tried various IOS images but same (or similar) behaviour.
Should this work.. All CCO references to IPv4+labels (unless related to IPv6 prefix / path distribution) explicitly state eBGP IPv4+labels, but our requirement is for IPv4+labels in conjuction with iBGP.
(If I try a similar schema using LDP - this works fine, but unfortunately LDP is not an option in the production network).
Also note, the link between devices is Ethernet,
I can appreciate why this may not work, but conversely I see no reason (except implementation) why this will not work.
Can someone please confirm whether this should work, and if so which version of IOS for the C7200.