Dell Brocade DCX, Руководство по настройке

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BigIron RX Series Configuration Guide 787
53-1001810-01
Using a table map to set the tag value
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The route-map <map-name> parameter specifies a route map to be consulted before adding the
static route to the BGP4 route table.
The route map you specify must already be configured on the router. Refer to “Defining route maps”
on page 798 for information about defining route maps.
Using a table map to set the tag value
Route maps that contain set statements change values in routes when the routes are accepted by
the route map. For inbound route maps (route maps that filter routes received from neighbors),
this means that the routes are changed before they enter the BGP4 route table.
For tag values, if you do not want the value to change until a route enters the IP route table, you can
use a table map to change the value. A table map is a route map that you have associated with the
IP routing table. The device applies the set statements for tag values in the table map to routes
before adding them to the route table.
To configure a table map, you configure the route map, then identify it as a table map. The table
map does not require separate configuration. You create it simply by calling an existing route map
a table map. You can have one table map.
NOTE
Use table maps only for setting the tag value. Do not use table maps to set other attributes. To set
other route attributes, use route maps or filters.
To create a route map and identify it as a table map, enter commands such as following. These
commands create a route map that uses an address filter. For routes that match the IP prefix list
filter, the route map changes the tag value to 100. This route map is then identified as a table map.
As a result, the route map is applied only to routes that the device places in the IP route table. The
route map is not applied to all routes. This example assumes that IP prefix list p11 has already
been configured.
BigIron RX(config)# route-map TAG_IP permit 1
BigIron RX(config-routemap TAG_IP)# match ip address prefix-list p11
BigIron RX(config-routemap TAG_IP)# set tag 100
BigIron RX(config-routemap TAG_IP)# router bgp
BigIron RX(config-bgp)# table-map TAG_IP
Changing the keep alive time and hold time
The Keep Alive Time specifies how frequently the router will send KEEPALIVE messages to its BGP4
neighbors. The Hold Time specifies how long the router will wait for a KEEPALIVE or UPDATE
message from a neighbor before concluding that the neighbor is dead. When the router concludes
that a BGP4 neighbor is dead, the router ends the BGP4 session and closes the TCP connection to
the neighbor.
The default Keep Alive time is 60 seconds. The default Hold Time is 180 seconds.
NOTE
Generally, you should set the Hold Time to three times the value of the Keep Alive Time.