White Papers

Table Of Contents
value, the more the route is preferred. The range is 0 to 4294967295. The default
is 100.
Defaults 100
Command Modes ROUTER BGP
Command
History
Version 8.2.1.0 Introduced on the E-Series ExaScale.
Version 7.4.1.0 Introduced
Usage
Information
The bgp default local-preference command setting is applied by all routers within the AS.
bgp enforce-first-as
Disable (or enable) enforce-first-as check for udates received from EBGP peers.
C-Series, E-Series
Syntax
bgp enforce-first-as
To turn off the default, use the no bgp enforce-first-as command.
Defaults Enabled.
Command Modes ROUTER BGP
Command
History
Version 8.2.1.0 Introduced on the E-Series ExaScale.
Version 7.4.1.0 Introduced
Usage
Information
This 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
incremented. Use the show ip bgp neighbors command to view the failed enforce-first-as check
counter.
If you disable enforce-first-as, you can view it using the show ip protocols command.
Related
Commands
show ip bgp neighbors views the information exchanged by BGP neighbors.
show ip protocols views information on routing protocols.
bgp fast-external-fallover
Enable the fast external fallover feature, which immediately resets the BGP session if a link to a directly connected external peer
fails.
C-Series, E-Series
Syntax
bgp fast-external-fallover
To disable fast external fallover, use the no bgp fast-external-fallover command.
Defaults Enabled.
Command Modes ROUTER BGP
Command
History
Version 8.2.1.0 Introduced on the E-Series ExaScale.
Version 7.4.1.0 Introduced
Border Gateway Protocol 429