Brocade Communications Systems FastIron SX 1600, Руководство по настройке, Страница: 472 / 593

• RFC 2918, which describes the dynamic route refresh capability
The dynamic route refresh capability is enabled by default and cannot be disabled. When the device sends a BGP4 OPEN message to a
neighbor, the device includes a Capability Advertisement to inform the neighbor that the device supports dynamic route refresh.
NOTE
The option for dynamically refreshing routes received from a neighbor requires the neighbor to support dynamic route refresh. If
the neighbor does not support this feature, the option does not take effect and the software displays an error message. The
option for dynamically re-advertising routes to a neighbor does not require the neighbor to support dynamic route refresh.
Dynamically refreshing routes
The following sections describe how to refresh BGP4 routes dynamically to put new or changed filters into effect.
To request a dynamic refresh of all routes from a neighbor, enter a command such as the following.
device(config-bgp-router)# clear ip bgp neighbor 192.168.1.170 soft in
This command asks the neighbor to send its BGP4 table (Adj-RIB-Out) again. The device applies its filters to the incoming routes and
adds, modifies, or removes BGP4 routes as necessary.
Syntax: clear ip bgp neighbor all | ip-addr | peer-group-name | as-num [ soft-outbound | soft [ in | out ] ]
The all , ip-addr , peer-group-name , and as-num parameters specify the neighbor. The ip-addr parameter specifies a neighbor by its IP
interface with the device. The peer-group-name specifies all neighbors in a specific peer group. The as-num parameter specifies all
neighbors within the specified AS. The all parameter specifies all neighbors.
The soft-outbound parameter updates all outbound routes by applying the new or changed filters, but sends only the existing routes
affected by the new or changed filters to the neighbor.
The soft in and soft out parameters specify whether you want to refresh the routes received from the neighbor or sent to the neighbor:
• soft in does one of the following:
– If you enabled soft reconfiguration for the neighbor or peer group, soft in updates the routes by comparing the route
policies against the route updates that the device has stored. Soft reconfiguration does not request additional updates from
the neighbor or otherwise affect the session with the neighbor.
– If you did not enable soft reconfiguration, soft in requests the entire BGP4 route table for the neighbor (Adj-RIB-Out), then
applies the filters to add, change, or exclude routes.
– If a neighbor does not support dynamic refresh, soft in resets the neighbor session.
• soft out updates all outbound routes, then sends the entire BGP4 router table for the device (Adj-RIB-Out) to the neighbor,
after changing or excluding the routes affected by the filters.
If you do not specify in or out , the device performs both options.
NOTE
The soft-outbound parameter updates all outbound routes by applying the new or changed filters, but sends only the existing
routes affected by the new or changed filters to the neighbor. The soft out parameter updates all outbound routes, then sends
the entire BGP4 route table for the device (Adj-RIB-Out) to the neighbor, after changing or excluding the routes affected by the
filters. Use
soft-outbound if only the outbound policy is changed.
To dynamically resend all the device BGP4 routes to a neighbor, enter a command such as the following.
device(config-bgp)# clear ip bgp neighbor 192.168.1.170 soft out
This command applies filters for outgoing routes to the device BGP4 route table (Adj-RIB-Out), changes or excludes routes accordingly,
then sends the resulting Adj-RIB-Out to the neighbor.
Displaying BGP4 information
FastIron Ethernet Switch Layer 3 Routing
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