Reference Guide

Border Gateway Protocol IPv4 (BGPv4) | 327
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
bgp four-octet-as-support
c e s
Enable 4-Byte support for the BGP process.
Syntax
bgp four-octet-as-support
To disable fast external fallover, enter no bgp four-octet-as-support.
Defaults
Disabled (supports 2-Byte format)
Command Modes
ROUTER BGP
Usage
Information
Routers supporting 4-Byte ASNs advertise that function in the OPEN message. The behavior of a
4-Byte router will be slightly different depending on whether it is speaking to a 2-Byte router or a
4-Byte router.
When creating Confederations, all the routers in the Confederation must be 4 or 2 byte identified
routers. You cannot mix them.
Where the 2-Byte format is 1-65535, the 4-Byte format is 1-4294967295. Both formats are accepted,
and the advertisements will reflect the entered format.
For more information about using the 2 or 4-Byte format, refer to the FTOS Configuration Guide.
Command
History
Version 7.7.1.0 Introduced support for C-Series
Version 7.4.1.0 Introduced
Version 7.8.1.0 Introduced support on S-Series
Version 7.7.1.0 Introduced support for C-Series
Version 7.8.1.0 Introduced support on S-Series
Version 7.7.1.0 Introduced command
Introduced support on C-Series