Dell Force10 C150 Configuration Manual page 212

Figure 10-4. BGP Best Path Selection
No, or Not Resulting in a Single Route
Highest
Highest
Weight
Local Pref
A Single Route is Selected and Installed in the Routing Table
Best Path selection details
1. Prefer the path with the largest WEIGHT attribute.
2. Prefer the path with the largest LOCAL_PREF attribute.
3. Prefer the path that was locally Originated via a
aggregate-address
• Routes originated with the
with the
4. Prefer the path with the shortest AS_PATH (unless the
configured, then AS_PATH is not considered). The following criteria apply:
• An AS_SET has a path length of 1, no matter how many ASs are in the set.
• A path with no AS_PATH configured has a path length of 0.
• AS_CONFED_SET is not included in the AS_PATH length.
212 | Border Gateway Protocol IPv4 (BGPv4)
Locally
Shortest
Originated
AS Path
Path
command.
network
aggregate-address
command.
Lowest
Lowest
Origin
MED
Code
network
command,
redistribute
or commands are preferred over routes originated
bgp bestpath as-path ignore
Lowest
Learned
NEXT-HOP
via EBGP
Cost
Tie Breakers
Lowest
Cluster ID
List
from
Lowest
Router ID
from
Lowest
Neighbor
Addr
redistribute
command or
command is