Configuring bgp filtering with route maps – Dell POWEREDGE M1000E User Manual

Page 947

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38-55

Cisco Catalyst Blade Switch 3130 and 3032 for Dell Software Configuration Guide

OL-13270-03

Chapter 38 Configuring IP Unicast Routing

Configuring BGP

Use the no form of each command to return to the default state.

Configuring BGP Filtering with Route Maps

Within BGP, route maps can control and modify routing information and t define the conditions by which
routes are redistributed between routing domains. See the

“Using Route Maps to Redistribute Routing

Information” section on page 38-95

for more information about route maps. Each route map has a name

that identifies the it (map tag) and an optional sequence number.

Beginning in privileged EXEC mode, follow these steps to use a route map to disable next-hop
processing:

Step 7

bgp bestpath med missing-as-worst

(Optional) Configure the switch to consider a missing
MED as having a value of infinity, making the path
without a MED value the least desirable path.

Step 8

bgp always-compare med

(Optional) Configure the switch to compare MEDs for
paths from neighbors in different autonomous systems. By
default, MED comparison is only done among paths in the
same autonomous system.

Step 9

bgp bestpath med confed

(Optional) Configure the switch to consider the MED in
choosing a path from among those advertised by different
subautonomous systems within a confederation.

Step 10

bgp deterministic med

(Optional) Configure the switch to consider the MED
variable when choosing among routes advertised by
different peers in the same autonomous system.

Step 11

bgp default local-preference value

(Optional) Change the default local-preference value. The
range is 0 to 4294967295; the default value is 100. The
highest local-preference value is preferred.

Step 12

maximum-paths number

(Optional) Configure the number of paths to be added to
the IP routing table. The default is to only enter the best
path in the routing table. The range is from 1 to 16. Having
multiple paths allows load-balancing among the paths.
(Although the switch software allows a maximum of
32 equal-cost routes, the switch hardware never uses more
than 16 paths per route.)

Step 13

end

Return to privileged EXEC mode.

Step 14

show ip bgp

show ip bgp neighbors

Verify the reset by reviewing routing table information
and BGP neighbor information.

Step 15

copy running-config startup-config

(Optional) Save your entries in the configuration file.

Command

Purpose

Command

Purpose

Step 1

configure terminal

Enter global configuration mode.

Step 2

route-map map-tag [[permit | deny] |
sequence-number]]

Create a route map, and enter route-map configuration mode.

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