Brocade FastIron Ethernet Switch Layer 3 Routing Configuration Guide - Manual (Page 468)

If the rib-route-limit command is configured to a value that is below the number of BGP4 routes
already installed in the RTM, the following warning message is displayed on the console.
device(config-bgp)# rib-route-limit 250
The new limit is below the current bgp rib route count. Please use Clear ip bgp
routes command to remove bgp rib routes.
You can only use one of the following commands to clear all BGP4 routes in the RTM, and reset the
routes for preferred BGP4 routes to be reinstalled in the RTM. Depending on the type of route the
rib-route-limit command is used for, select from one of the following commands:
• clear ip bgp routes command. This command is used to clear IPv4 BGP unicast routes.
• clear ipv6 bgp routes command. This command is used to clear IPv6 BGP unicast routes.
NOTE
It is not guaranteed that the same number of preferred BGP4 routes will be reinstalled in the RTM.
4. Perform the following step to:
• exit the BGP4 unicast family configuration.
device(config-bgp-ipv4u)#exit-address-family
Syntax: exit-address-family
When you enter the exit-address-family command at the address family configuration level, you
return to the BGP4 unicast address family configuration level (the default BGP4 level).
Displaying configuration for BGP route reflector
To display the configuration for preferred BGP4 routes not installed in the RTM, use the show ip bgp
route command as shown in the following example.
device(config-bgp)# show ip bgp route
Total number of BGP Routes: 333422
Status A:AGGREGATE B:BEST b:NOT-INSTALLED-BEST C:CONFED_EBGP D:DAMPED
E:EBGP H:HISTORY I:IBGP L:LOCAL M:MULTIPATH m:NOT-INSTALLED-MULTIPATH
S:SUPPRESSED F:FILTERED s:STALE
Prefix Next Hop MED LocPrf Weight Status
...5 10.12.0.0/24 10.100.100.4 100 0 E
AS_PATH:48 1994 65148 21948 6461 1239 4837 4808 17431 18245...
Syntax: show ip bgp route
In the previous output, BGP4 receives 333,422 routes and the rib-route-limit command is configured
to 300,000 routes. The always-propagate command has not been enabled. However, because the
rib-route-limit command is configured to allow for 300,000 routes in the RTM, BGP4 installs only
300,000 routes of the 333,422 routes received in the RTM. When the always-propagate command is
enabled, a preferred BGP4 route not installed in the RTM is now considered as the best BGP4 route to
be advertised to other peers. The route is identified by the letter "b" (for NOT-INSTALLED-BEST) in
the Status field. However, when the always-propagate command is not enabled, the status field
displays only the default letter "E", as displayed for BGP4 route 10.12.0.0/24. The letter "B" or "b" is
missing from the Status field.
NOTE
The description of the status "b: NOT-INSTALLED-BEST" has changed. The status description for "b:
NOT-INSTALLED-BEST" is now: The routes received from the neighbor are the best BGP4 routes to
their destinations, but were nonetheless not installed in the IP route table due to the rib-route-limit
option (or RTM route table size limit), and the always-propagate option to allow the propagating of
those best BGP routes.
Displaying configuration for BGP route reflector
468 FastIron Ethernet Switch Layer 3 Routing Configuration Guide
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