HP VPN Firewall Appliances Network Management Configuration Guide

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Troubleshooting BGP
Symptom
Display BGP peer information by 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 must establish a TCP session using port 179 and exchange Open
messages successfully.
Solution
1. Use the display current-configuration command to verify that the peer's AS number is correct.
2. Use the display bgp peer command to verify that the peer's IP address is correct.
3. If a loopback interface is used, verify that the loopback interface is specified with the peer
connect-interface command.
4. If the peer is a non-direct EBGP peer, verify that the peer ebgp-max-hop command is configured.
5. If the peer ttl-security hops command is configured, verify that the command is configured on the
peer, and the hop-count values configured on them are greater than the number of hops between
them.
6. Verify that a valid route to the peer is available.
7. Use the ping command to verify the connectivity to the peer.
8. Use the display tcp status command to verify the TCP connection.
9. Verify whether an ACL is applied to disable TCP port 179.