Troubleshooting Bgp; No Bgp Peer Relationship Established - 3Com S7906E Configuration Manual

# Configure IP addresses for interfaces (omitted).
# Configure the iBGP connection.
<SwitchB> system-view
[SwitchB] bgp 65009
[SwitchB-bgp] router-id 3.3.3.3
[SwitchC-bgp] peer 9.1.1.1 as-number 65009
# Redistribute direct routes.
[SwitchC-bgp] import-route direct
# Enable GR capability for BGP.
[SwitchC-bgp] graceful-restart
Verification
When an active/standby main board switchover occurs on Switch B, Switch A and Switch C can still
ping each other,

Troubleshooting BGP

No BGP Peer Relationship Established

Symptom
Display BGP peer information using the display bgp peer command. The state of the connection to a
peer cannot become established.
Analysis
To become BGP peers, any two routers need to establish a TCP session using port 179 and exchange
Open messages successfully.
Solution
1) Use the display current-configuration command to verify the peer's AS number.
2) Use the display bgp peer command to verify the peer's IP address.
3) If the loopback interface is used, check whether the peer connect-interface command is
configured.
4) If the peer is a non-direct eBGP peer, check whether the peer ebgp-max-hop command is
configured.
5) Check whether a route to the peer is available in the routing table.
6) Use the ping command to check connectivity.
7) Use the display tcp status command to check the TCP connection.
8) Check whether an ACL disabling TCP port 179 is configured.
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