Concept Guide

Last read 00:00:00, Last write 00:00:07
Hold time is 90, keepalive interval is 30 seconds
Received 18 messages, 0 in queue
7 opens, 6 notifications, 0 updates
5 keepalives, 0 route refresh requests
Sent 26 messages, 0 in queue
7 opens, 0 notifications, 0 updates
19 keepalives, 0 route refresh requests
Route refresh request: received 0, sent messages 0
Minimum time between advertisement runs is 30 seconds
Minimum time before advertisements start is 0 seconds
For address family: IPv4 Unicast
BGP local RIB : Routes to be Added 0, Replaced 0, Withdrawn 0
InQ : Added 0, Replaced 0, Withdrawn 0
OutQ : Added 0, Withdrawn 0
Allow local AS number 0 times in AS-PATH attribute
Prefixes accepted 0, withdrawn 0 by peer, martian prefixes ignored 0
Prefixes advertised 0, denied 0, withdrawn 0 from peer
Connections established 0; dropped 0
Last reset never
No active TCP connection
Enabling four-byte autonomous system numbers
You can enable 4-byte support for conguring autonomous system numbers (ASN).
To enable 4-byte support for the BGP process, use the following command.
NOTE
: When creating BGP confederations, all the routers in the Confederation must be a 4-byte or 2-byte identied routers. You
cannot mix them.
• Enable 4-byte support for the BGP process.
CONFIG-ROUTER-BGP mode
bgp four-octect-as-support
NOTE
: If you enter a 4-byte AS number, 4-byte AS support is enabled automatically. This command is optional. Use it only
if you support 4-Byte AS numbers or if you support AS4 number representation.
Disable 4-Byte support and return to the default 2-Byte format by using the no bgp four-octet-as-support command. You
cannot disable 4-Byte support if you currently have a 4-Byte ASN congured.
Example conguration for enabling four-byte autonomous system numbers
DellEMC# configure terminal
DellEMC(conf)# router bgp 80000
DellEMC(conf-router_bgp)# bgp four-octet-as-support
DellEMC(conf-router_bgp)# neighbor 20.20.20.1 remote-as 200
DellEMC(conf-router_bgp)# neighbor 20.20.20.1 no shutdown
DellEMC(conf-router_bgp)#exit
To view BGP conguration, use the show running-config bgp command in EXEC Privilege mode.
The following example shows the show ip bgp summary command output (4–byte AS number displays).
R2#show ip bgp summary
BGP router identifier 1.1.1.1, local 80000
BGP local RIB : Routes to be Added 0, Replaced 0, Withdrawn 0
1 neighbor(s) using 40960 bytes of memory
Neighbor AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/Pfx
20.20.20.1 200 0 0 0 0 0 00:00:00 0
202
Border Gateway Protocol (BGP)