On Wed, Jul 26, 2017 at 12:20:29PM +0100, Israel G. Lugo wrote:
Hello,
What I need, unless someone has a better suggestion, is some way to summarize externals in OSPF, such that the summary prefix is only announced if I've got more specific routes inside it.
Hi
area 0.0.1.2 { nssa; /* transit VLAN to the tennant routers */ interface "eth0.22" { stub; check link yes; }; external { 198.18.0.0/15; }; }
From my understanding, I believe the external keyword on an NSSA would be to aggregate in the opposite direction (backbone -> NSSA area).
No, it is used for aggregation in NSSA->backbone direction. But it works only for NSSA-ext routes received from the NSSA area. If you export external route to OSPF on ABR, it is always exported directly to backbone (regardless of its nexthop).
Is there any way to do what I want? I.e., summarize externals into OSPF, if and only if I have specific routes inside the summary prefix? That, or a conditional route, that only gets inserted if another certain route exists, or if the BGP peering is up.
Not directly, you can use the trick with with recursive route: http://bird.network.cz/pipermail/bird-users/2017-July/011408.html -- Elen sila lumenn' omentielvo Ondrej 'Santiago' Zajicek (email: santiago@crfreenet.org) OpenPGP encrypted e-mails preferred (KeyID 0x11DEADC3, wwwkeys.pgp.net) "To err is human -- to blame it on a computer is even more so."