diff options
| author | Donatas Abraitis <donatas@opensourcerouting.org> | 2024-09-13 10:51:41 +0300 |
|---|---|---|
| committer | Donatas Abraitis <donatas@opensourcerouting.org> | 2024-09-13 10:51:41 +0300 |
| commit | cadfa693d618f56c9fcffd2cd227917f15953711 (patch) | |
| tree | ac4c6e3d179b0078c343561cf6884746a6374416 /bgpd/bgp_packet.c | |
| parent | bf1fa1b2dfeebb4fefcf3655111f30a766b6bc6d (diff) | |
bgpd: Implement BGP dual-as feature
This is helpful for migrations, etc.
The neighbor is configured with:
```
router bgp 65000
neighbor X local-as 65001 no-prepend replace-as dual-as
```
Neighbor X can use either 65000, or 65001 to peer with.
Closes: https://github.com/FRRouting/frr/issues/13928
Signed-off-by: Donatas Abraitis <donatas@opensourcerouting.org>
Diffstat (limited to 'bgpd/bgp_packet.c')
| -rw-r--r-- | bgpd/bgp_packet.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/bgpd/bgp_packet.c b/bgpd/bgp_packet.c index fa03f1d21d..62be7ffbf7 100644 --- a/bgpd/bgp_packet.c +++ b/bgpd/bgp_packet.c @@ -2702,6 +2702,19 @@ static int bgp_notify_receive(struct peer_connection *connection, inner.subcode == BGP_NOTIFY_OPEN_UNSUP_PARAM) UNSET_FLAG(peer->sflags, PEER_STATUS_CAPABILITY_OPEN); + /* Resend the next OPEN message with a global AS number if we received + * a `Bad Peer AS` notification. This is only valid if `dual-as` is + * configured. + */ + if (inner.code == BGP_NOTIFY_OPEN_ERR && + inner.subcode == BGP_NOTIFY_OPEN_BAD_PEER_AS && + CHECK_FLAG(peer->flags, PEER_FLAG_DUAL_AS)) { + if (peer->change_local_as != peer->bgp->as) + peer->change_local_as = peer->bgp->as; + else + peer->change_local_as = peer->local_as; + } + /* If Graceful-Restart N-bit (Notification) is exchanged, * and it's not a Hard Reset, let's retain the routes. */ |