BGP Neighbor States

- idel

The BGP process either administratively down or awaiting the next retry attempt.

- Connet

The BGP process process is waiting for the TCP connection to be completed. You can not determine from this state information whether the TCP connection can complete.

- Active

The TCP connection has been completed, but no BGP message had been yet sent to your peer

- Opensent

The TCP connection exist, BGP Open message has been sent to the peer, but the matching Open message has not yet been received from the other router.

- Openconfirm

An Open message has been both sent to and received from the other router. The next step is to receive a BFP Keepalive message(to confirm that all neighbor-related parameters match) or a BFP Notification message (to learn that there is some mismatch in neighbor parameters). 

- Established

All neighbor parameters match, the neighbor relationship works, and the  peers can now exchange Update messages.