Dell PowerEdge FN I/O Module Command Line Reference Guide 9.10(0.0)

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bgp enforce-first-as

Disable (or enable) enforce-first-as check for updates received from EBGP peers.

Syntax

bgp enforce-first-as

To turn off the default, use the no bgp enforce-first-as command.

Defaults

Enabled

Command Modes

ROUTER BGP

Supported Modes

Full–Switch

Command History

Version	Description
9.9(0.0)	Introduced on the FN IOM.
9.2(0.0)	Introduced on the MXL 10/40GbE Switch IO Module.

Usage Information

This command 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 increments. To view the “failed enforce-first-as check” counter, use the show ip bgp neighbors command.

If you disable the enforce-first-as command, it can be viewed using the show ip protocols command.

Related Commands

show ip bgp neighbors — views the information the BGP neighbors exchange.

show ip protocols — views information on routing protocols.