[c-nsp] Converting OSPF backbone to iBGP

[Garry]

Hi,

after years of running very smoothly and without any problems (and not
expecting any), we have decided to move our backbone from OSPF (single
area) to iBGP as far as "best practice" recommendations go ... I've been
trying to find decent write-ups about certain things, but haven't been
too successful as far as certain details go ... maybe somebody has some
good pointers for me ...

OK, so baseline recommendation is to only transport loopback/interface
IPs in OSPF, do everything else via iBGP ...

Now, we already have two route reflectors running which we use for MPLS
VRF connectivity, so moving everything else over to them shouldn't be
too much of a problem ...

For the basic stuff I'm not worried much, dropping the "redistribute
static/connected subnets" isn't much of a problem, neither is adding the
connected/static routes to the local BGP network statements ... problem
is several devices that do not speak BGP ... e.g. two Ascend MAX routers
that terminate ISDN PRI lines - they don't speak BGP, so all I can do is
let them continue in OSPF ... what would I need to do to get them into
the iBGP setup decently? Please note that apart from the dynamic IPs
from a certain pool they also hand out static IPs for ISDN dial backup,
so just statically routing certain IP ranges to them isn't an option ...
which means I need to do some kind of export from OSPF into iBGP for
those boxes by some other boxes (every POP/backbone site has Cisco
backbone boxes, so appropriate HW is available)

Also, we have CPE devices that speak OSPF to our equipment in order to
set up dual uplinks to customer sites ... usually one link is a
"regular" leased line to one POP/Backbone site, whereas the second is a
DSL link where the terminating LAC (at another POP/Backbone site)
currently announces the customer routes into OSPF with lower priority
... so I need a way of getting them OSPF informations into iBGP without
it making its way into the OSPF backbone ...

Any ideas or pointers?

Thanks!