On 2/6/24 18:48, Lee Starnes via juniper-nsp wrote:
Hello everyone, I was having difficulty in getting an announcement of a IPv6 /32 block using prefix-lists rather than redistribution of the IP addresses in from other protocols. We only have a couple /64 blocks in use at the moment but want to be able to announce the entire /32. In cisco, that would just be a holddown route and then announce. Not sure how it works to Juniper. I configured a prefix-list that contained the /32 block in it. Then created a policy statement with term 1 from prefix-list <list> and then term 2 then accept. Set the export in BGP protocol peer of this policy statement and it just ignores it. Now this same setup in IPv4 works fine. After a week of going round and round with Juniper TAC, they had me setup a rib inet6 aggregate entry for the /32 and then use that in the policy statement.
This is the equivalent of the "hold-down" route you refer to in Cisco-land. Useful if the route does not exist in the RIB from any other source.
I'm guessing your IPv4 route just works without a hold-down route because it is being learned from somewhere else (perhaps your IGP, iBGP or a static route), and as such, already exists in the router's RIB for your export policy to pick it up with no additional fiddling.
Typically, BGP will not originate a route to its neighbors unless it already exists in the routing table through some source. If it is an aggregate route, a hold-down pointing to "discard" (Null0 in Cisco) is enough. If it is a longer route assigned to a customer, that route pointing to the customer will do.
Mark. _______________________________________________ juniper-nsp mailing list juniper-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/juniper-nsp
