Users Guide

The fast external fallover conguration is applied only after you manually reset all the existing BGP sessions.
As a result, after you execute this command, you must also manually execute the clear ip bgp
command in order for the conguration to take eect.
bgp four-octet-as-support
Enable 4-byte support for the BGP process.
S4820T
Syntax
bgp four-octet-as-support
To disable fast external failover, use the no bgp four-octet-as-support command.
Defaults Disabled (supports 2–byte format)
Command Modes ROUTER BGP
Command History
This guide is platform-specic. For command information about other platforms, refer to the relevant Dell
Networking OS Command Line Reference Guide.
The following is a list of the Dell Networking OS version history for this command.
Version Description
9.8(0.0P5) Introduced on the S4048-ON.
9.8(0.0P2) Introduced on the S3048-ON.
9.7(0.0) Introduced on the S6000–ON.
9.2(1.0) Introduced on the Z9500.
9.0.2.0 Introduced on the S6000.
8.3.19.0 Introduced on the S4820T.
8.3.11.1 Introduced on the Z9000.
8.3.7.0 Introduced on the S4810.
7.8.1.0 Introduced on the S-Series.
7.7.1.0 Introduced on the C-Series.
Usage Information
Routers supporting 4-byte ASNs advertise that function in the OPEN message. The behavior of a 4-byte
router is slightly dierent 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 byte or 2 byte identied
routers. You cannot mix them.
Where the 2-byte format is from 1 to 65535, the 4-byte format is from 1 to 4294967295. Both formats are
accepted and the advertisements reect the entered format.
For more information about using the 2 byte or 4-byte format, refer to the Dell Networking OS
Conguration Guide.
This command automatically restarts the BGP instance for the conguration to take eect.
Border Gateway Protocol
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