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Usage
Information
All routers apply the bgp default local-preference command setting within the AS. To set
the local preference for a specific route, use the set local-preference command in ROUTE-MAP
mode.
Related
Commands
set metric — assigns a local preference value for a specific route.
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.
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.
Syntax
bgp fast-external-failover
To disable fast external failover, use the no bgp fast-external-failover 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
The bgp fast-external-failover command appears in the show config command output.
264 Border Gateway Protocol IPv4 (BGPv4)