Dynamically refreshing routes – Brocade Multi-Service IronWare Routing Configuration Guide (Supporting R05.6.00) User Manual
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Multi-Service IronWare Routing Configuration Guide
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Filtering
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RFC 2842. This RFC specifies the Capability Advertisement, which a BGP4 device uses to
dynamically negotiate a capability with a neighbor.
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RFC 2858 for Multi-protocol Extension.
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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.
Brocade(config-bgp)# 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 | 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 | out] parameter specifies whether you want to refresh the routes received from the
neighbor or sent to the neighbor:
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soft in does one of the following:
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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. Refer to
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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.
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If a neighbor does not support dynamic refresh, soft in resets the neighbor session.
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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.