Configuring Bgp Route Attributes - 3Com Switch 4800G 24-Port Configuration Manual

386 C 30: BGP C
HAPTER
Enabling BGP and IGP
Route Synchronization
Configuring BGP Route
Dampening
Configuring BGP
Route Attributes
Prerequisites
Configuration Procedure
ONFIGURATION
By default, when a BGP router receives an IBGP route, it only checks the
reachability of the route's next hop before advertisement. With BGP and IGP
synchronization configured, the BGP router cannot advertise the route to EBGP
peers unless the route is also available in the IGP routing table.
Follow these steps to configure BGP and IGP synchronization:
To do...
Enter system view
Enter BGP view
Enable synchronization
between BGP and IGP
By configuring BGP route dampening, you can suppress unstable routes from
neither adding them to the local routing table nor advertising them to BGP peers.
Follow these steps to configure BGP route dampening:
To do...
Enter system view
Enter BGP view
Configure BGP route
dampening
Before configuring this task, you have configured BGP basic functions.
You can configure BGP route attributes to influence BGP route selection.
Follow these steps to configure BGP route attributes:
To do...
Enter system view
Enter BGP view
Configure preferences for external,
internal, local routes
Configure the default local preference
Use the command...
system-view
bgp as-number
synchronization
Use the command...
system-view
bgp as-number
dampening [ half-life-reachable
half-life-unreachable reuse suppress
ceiling | route-policy
route-policy-name ] *
Use the command...
system-view
bgp as-number
preference
{ external-preference
internal-preference
local-preference |
route-policy
route-policy-name }
default local-preference
value
Remarks
-
-
Required
Not enabled by default
Remarks
-
-
Optional
Not configured by default
Remarks
-
-
Optional
The default
preferences of
external, internal,
and local routes are
255, 255, and 130
respectively.
Optional
100 by default