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Example of the show ip bgp neighbor Command to View Last and Bad PDUs
Dell(conf-router_bgp)#do show ip bgp neighbors 1.1.1.2
BGP neighbor is 1.1.1.2, remote AS 2, external link
BGP version 4, remote router ID 2.4.0.1
BGP state ESTABLISHED, in this state for 00:00:01
Last read 00:00:00, last write 00:00:01
Hold time is 90, keepalive interval is 30 seconds
Received 1404 messages, 0 in queue
3 opens, 1 notifications, 1394 updates
6 keepalives, 0 route refresh requests
Sent 48 messages, 0 in queue
3 opens, 2 notifications, 0 updates
43 keepalives, 0 route refresh requests
Minimum time between advertisement runs is 30 seconds
Minimum time before advertisements start is 0 seconds
Capabilities received from neighbor for IPv4 Unicast :
MULTIPROTO_EXT(1)
ROUTE_REFRESH(2)
CISCO_ROUTE_REFRESH(128)
Capabilities advertised to neighbor for IPv4 Unicast :
MULTIPROTO_EXT(1)
ROUTE_REFRESH(2)
CISCO_ROUTE_REFRESH(128)
For address family: IPv4 Unicast
BGP table version 1395, neighbor version 1394
Prefixes accepted 1 (consume 4 bytes), 0 withdrawn by peer
Prefixes advertised 0, rejected 0, 0 withdrawn from peer
Connections established 3; dropped 2
Last reset 00:00:12, due to Missing well known attribute
Notification History
'UPDATE error/Missing well-known attr' Sent : 1 Recv: 0
'Connection Reset' Sent : 1 Recv: 0
Last notification (len 21) sent 00:26:02 ago
ffffffff ffffffff ffffffff ffffffff 00160303 03010000
Capturing PDUs
To capture incoming and outgoing PDUs on a per-peer basis, use the capture bgp-pdu neighbor direction command. To
disable capturing, use the no capture bgp-pdu neighbor direction command.
The buer size supports a maximum value between 40MB (the default) and 100MB. The capture buers are cyclic and reaching the limit
prompts the system to overwrite the oldest PDUs when new ones are received for a given neighbor or direction. Setting the buer size to
a value lower than the current maximum, might free captured PDUs to set the new limit.
NOTE
: Memory on RP1 is not pre-allocated and is allocated only when a PDU needs to be captured.
The buers storing the PDU free memory when:
• BGP is disabled.
• A neighbor is uncongured.
• The clear ip bgp command is issued.
• New PDUs are captured and there is no more space to store them.
• The max buer size is reduced. (This may clear PDUs depending on the buer space consumed and the new limit.)
Border Gateway Protocol IPv4 (BGPv4)
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