Reference Guide

Border Gateway Protocol IPv4 (BGPv4) | 319
Syntax
bgp enforce-first-as
To turn off the default, use the no bgp enforce-first-as command.
Defaults
Enabled
Command Modes
ROUTER BGP
Usage
Information
This is enabled by default, that is for all updates received from EBGP peers, BGP
ensures that the first AS of the first AS segment is always the AS of the peer. If not,
the update is dropped and a counter is incremented. Use the show ip bgp neighbors
command to view the “failed enforce-first-as check counter.
If enforce-first-as is disabled, it can be viewed via the show ip protocols command.
Related
Commands
Command
History
bgp fast-external-fallover
c e s
Enable the fast external fallover feature, which immediately resets the BGP session if
a link to a directly connected external peer fails.
Syntax
bgp fast-external-fallover
To disable fast external fallover, enter no bgp fast-external-fallover.
Defaults
Enabled.
Command Modes
ROUTER BGP
Usage
Information
The bgp fast-external-fallover command appears in the show config command
output.
Command
History
show ip bgp neighbors View the information exchanged by BGP neighbors
show ip protocols View Information on routing protocols.
Version 8.3.19.0 Introduced on the S4820T.
Version 8.3.7.0 Introduced on the S4810.
Version 7.8.1.0 Introduced support on S-Series
Version 7.7.1.0 Introduced support for C-Series
Version 7.4.1.0 Introduced
Version 8.3.19.0 Introduced on the S4820T.
Version 8.3.7.0 Introduced on the S4810.
Version 7.8.1.0 Introduced support on S-Series
Version 7.7.1.0 Introduced support for C-Series