Yes, you are correct. In a NAP configuration that is changing this probably would be difficult to avoid. -----Original Message----- From: Alex Bligh To: nanog@merit.edu Cc: amb@gxn.net Sent: 2/10/99 12:37 AM Subject: Multiple BGP sessions between the same router pairs at IXPs Anyone feel like sanity checking this for me: As far as I know, if you have this config RTRA BGP ID 4.4.4.4 ASN 4 2.2.2.4 / \ 3.3.3.4 2.2.2.0/24 | | 3.3.3.0/24 2.2.2.5 \ / 3.3.3.5 RTRB BGP ID 5.5.5.5 ASN 5 and you configure on router A router bgp 4 neighbor 2.2.2.5 remote-as 5 nieghbor 3.3.3.5 remote-as 5 and on router B router bgp 5 neighbor 2.2.2.4 remote-as 4 nieghbor 3.3.3.4 remote-as 4 then only one peering session will come up, as routers only support one BGP session with any given router ID. We hit this problem when renumbering the LINX, I think, in that you have to make sure you take down old sessions to get new sessions to work. This would also affect people who set up new peerings over the ATM MAE's, who also have existing peerings on the FDDI fabric between the same routers, right? -- Alex Bligh GX Networks (formerly Xara Networks)