No relevant resource is found in the selected language.

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies. Read our privacy policy>

Reminder

To have a better experience, please upgrade your IE browser.

upgrade

FAQ: What Are Meanings of Common BGP Status?

Publication Date:  2013-09-03 Views:  56 Downloads:  0
Issue Description
What are meanings of common BGP status?
Handling Process

N/A

Root Cause

N/A

Solution

1. Idle state
A BGP peer enters the Idle state first after a BGP connection is established. The BGP is waiting for a startup event. Upon a startup event, the BGP peer initializes resources, resets the Connect-Retry timer, initiates a TCP connection, and enters the Connect state.
2. Connect state
In Connect state, the BGP peer initiates the first TCP connection. If the Connect-Retry timer times out, the BGP peer re-initiates a TCP connection and remains in Connect state. If the TCP connection is established, the BGP peer enters the OpenSent state. If the TCP connection fails to be established, the BGP peer enters the Active state.
3. Active state
In Active state, the BGP peer attempts to establish a TCP connection. If the Connect-Retry timer times out, the BGP peer returns to the Connect state. If the TCP connection is established, the BGP peer enters the OpenSent state. If the TCP connection fails to be established, the BGP peer remains in Active state and continues initiating TCP connections.
4. OpenSent state
In OpenSent state, the BGP peer has established a TCP connection and sent the first Open message. The BGP peer waits for an Open message from its peer. In addition, the BGP peer checks the validity of the received Open message. If an error is detected, the BGP peer sends an error notification message and returns to Idle state. If no error is detected, the BGP peer sends Keepalive messages, resets the keepalive timer, and enters the OpenConfirm state.
[NE40E-bgp]disp bgp peer
 BGP local router ID : 1.1.1.111
 Local AS number : 100
 Total number of peers : 1                Peers in established state : 0
  Peer            V    AS  MsgRcvd  MsgSent  OutQ  Up/Down       State PrefRcv
  100.0.15.2      4   200        0        1     0 00:00:32    OpenSent       0
5. OpenConfirm state
In OpenConfirm state, the BGP peer waits for a Keepalive message and resets the hold timer. After receiving a Keepalive message, the BGP peer enters the Established state. That is, a BGP peer relationship is established. If the TCP connection is disconnected, the BGP peer returns to the Idle state.
6. Established state
In Established state, the BGP peer relationship is established. The BGP peer exchanges Update messages with its peer and resets the hold timer.
7. Idle(Admin) state
In Idle(Admin) state, the BGP peer is shut down and does not attempt to establish a TCP connection. For example, if the peer ignore command is executed, the BGP peer enters the Idle(Admin) state.
[NE40E-bgp]disp bgp peer
 BGP local router ID : 1.1.1.111
 Local AS number : 100
 Total number of peers : 1                Peers in established state : 0
  Peer            V    AS  MsgRcvd  MsgSent  OutQ  Up/Down       State PrefRcv
  100.0.15.2      4   200        0        1     0 00:00:32    Idle(Admin)       0
8.
No neg:
In No neg state, the capability of a BGP peer is not negotiated.
For example, when only one peer is configured with VPNv4, the other peer that is not configured with VPNv4 enters the No neg state.
<NE40E>disp bgp vpnv4 all peer                                                     
                                                                                
 BGP local router ID : 1.1.1.1                                                  
 Local AS number : 100                                                          
 Total number of peers : 1                 Peers in established state : 0       
                                                                                
  Peer            V    AS  MsgRcvd  MsgSent  OutQ  Up/Down       State PrefRcv  
                                                                                
  2.2.2.2         4   100       42       46     0 00:33:28      No neg       0 

END