Concept Guide

• Disable next hop processing and congure the router as the next hop for a BGP neighbor.
CONFIG-ROUTER-BGP mode
neighbor {ip-address | peer-group-name} next-hop-self
• Sets the next hop address.
CONFIG-ROUTE-MAP mode
set next-hop ip-address
Changing the WEIGHT Attribute
To change how the WEIGHT attribute is used, enter the rst command. You can also use route maps to change this and other BGP
attributes. For example, you can include the second command in a route map to specify the next hop address.
• Assign a weight to the neighbor connection.
CONFIG-ROUTER-BGP mode
neighbor {ip-address | peer-group-name} weight weight
– weight: the range is from 0 to 65535.
The default is 0.
• Sets weight for the route.
CONFIG-ROUTE-MAP mode
set weight weight
– weight: the range is from 0 to 65535.
To view BGP conguration, use the show config command in CONFIGURATION ROUTER BGP mode or the show running-
config bgp command in EXEC Privilege mode.
Enabling Multipath
By default, the software allows one path to a destination. You can enable multipath to allow up to 16 parallel paths to a destination.
To allow more than one path, use the following command.
The show ip bgp network command includes multipath information for that network.
• Enable multiple parallel paths.
CONFIG-ROUTER-BGP mode
maximum-paths {ebgp | ibgp} number
The show ip bgp network command includes multipath information for that network.
Filtering BGP Routes
Filtering routes allows you to implement BGP policies.
You can use either IP prex lists, route maps, AS-PATH ACLs or IP community lists (using a route map) to control which routes the BGP
neighbor or peer group accepts and advertises. Prex lists lter routes based on route and prex length, while AS-Path ACLs lter routes
based on the ASN. Route maps can lter and set conditions, change attributes, and assign update policies.
NOTE
: The Dell Networking OS supports up to 255 characters in a set community statement inside a route map.
208 Border Gateway Protocol IPv4 (BGPv4)