[j-nsp] Logical router to master router

[nachocheeze at gmail.com]

I have a couple of M-series routers that were for valid-at-the-time
reasons rolled out with the master routing instance being on a
non-public (i.e. real IP's, but not connected to  the Internet)
network.  They currently serve about 20 private customers, with
varying degrees of policy complexity.

As life happened, these boxes wound up going into a position where
they became connected to the Internet and providing services to
downstream public customers, with the public ASN, netblocks, etc
living inside a logical router (separate ASN, connectors, routing
policies, etc).  As things have expanded, lack of ability to
administer various items that don't work inside a logical router
(SNMP, NetFlow, etc) has started biting me in ass.

I would like to basically just flip the config and put the "private"
routing domain into a logical router, and move the "Internet" logical
router configuration over into the master routing instance.  That's
pretty serious undertaking given all the stuff that has to migrate, so
I'm curious if anyone's ever done this and your experiences.  In a
perfect world, I'd just get a couple of *spare* routers, set them
properly, and just migrate the physical connections, but that isn't
going to happen; if I do it, it's going to have to happen pretty much
"live".

Has anyone ever done this, and apart from the obvious (fat-fingering
ASN's, IP's, etc), are there any "gotchas" of which I should be aware
or tips on the easiest way to do this?