Limitation on stubnet prefixes
Andre Cunha
andre_novaes at yahoo.com
Fri Jul 26 15:32:04 CEST 2019
Thanks Ondrej, that makes sense. Is there a way to add routes on the fly then, instead of putting them all in the config file? Or any other suggestion on how I could generate 50000 type-1 LSA.
Regards
Andre
On 26/07/2019, 12:32, "Ondrej Zajicek" <santiago at crfreenet.org> wrote:
On Fri, Jul 26, 2019 at 10:49:31AM +0200, Andre Cunha wrote:
> Hello,
>
> Is there a limit on the number of stubnet prefixes that we can configure? I have configured 50000 stubnets but my router receives only 1084 routes.
Hello
Yes, stubnet prefixes are announced as a part of the Router-LSA, with
12 B per prefix. With 16bit Router-LSA length, the limit is about 5400
Router-LSA entries (including other entries than just stubnets). But note
that having such large Router-LSA may cause many problems, including OSPF
packet fragmentation, so i would generally suggest to not have larger
Router-LSA than MTU, i.e. not more than ~100 entries.
This length limit is not enforced in BIRD, if you configure more
stubnets, the Router-LSA with length modulo 64k is generated, which
may be invalid. I should add some check and warning there.
External routers are announced as separate External-LSAs, so there is no
such limit for them.
--
Elen sila lumenn' omentielvo
Ondrej 'Santiago' Zajicek (email: santiago at 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."
More information about the Bird-users
mailing list