Users Guide

Usage Information
This command is enabled by default, that is for all updates received from EBGP peers, BGP ensures that the
rst AS of the rst AS segment is always the AS of the peer. If not, the update is dropped and a counter is
increments. Use the show ip bgp neighbors command to view the “failed enforce-rst-as check”
counter.
If you disable the enforce-first-as command, it can be viewed using the show ip protocols
command.
In the event of an enfore-rst-as check failure, the existing BGP session is apped.
Related Commands
show ip bgp neighbors — views the information the BGP neighbors exchange.
show ip protocols — views information on routing protocols.
bgp fast-external-failover
Enable the fast external failover feature, which immediately resets the BGP session if a link to a directly connected external peer fails.
S5000
Syntax
bgp fast-external-failover
To disable fast external failover, use the no bgp fast-external-failover command.
Defaults Enabled
Command Modes ROUTER BGP
Command History
Version 9.0(1.3) Introduced on the S5000.
Usage Information
The bgp fast-external-failover command appears in the show config command output.
bgp four-octet-as-support
Enable 4-byte support for the BGP process.
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.
Border Gateway Protocol
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