UMN:CLI
User Manual
V5824G
396
10.1.2.4
Local Preference
The local preference indicates the preferred path when there are multiple paths to the
same destination. The path having a higher preference is preferred.
To define preference of a particular path, use the following command.
Command
Mode
Description
bgp
default local-preference
<0-
4294967295>
Router
Defines preference of a particular path and it is sent to
all routers and access servers in the local AS.
0-4294967295: local preference value (default: 100)
no bgp
default local-preference
Deletes the defined preference and reverts to the
default setting.
10.1.2.5
Multi-Exit Discriminator (MED)
During the best-path selection process, the switch compares weight, local preference and
as-path in turn among the similar parameters of BGP routers. Then, the MED is
considered when selecting the best path among many alternative paths.
The V5824G, MED comparison is configured only among all paths from the autonomous
system. You can configure the comparison of MEDs among all BGP routers within
autonomous system. In addition, MED is used when comparing of routes from the
neighboring routers placed within different AS.
To find the best route by comparing MED values, use the following command.
Command
Mode
Description
bgp always-compare-med
Router
Configures the router to consider the comparison of
MEDs in choosing the best path from among paths.
no bgp always-compare-med
Chooses the best path regardless of the comparison of
MEDs.
Meanwhile, when the best-path is selected among the neighbor routers within same
Autonomous System, it doesn
’t compare MED values of them. However, in case the
paths have same AS-path information, it does compare MED values. If there are two
paths with different AS-path each other, the comparison of MED is unnecessary work.
Other parameter
’s path information can be used to find the best path.
To compare MED values in order to choose the best path among lots of alternative paths
included same AS-path value, use the following command.
Command
Mode
Description
bgp deterministic-med
Router
Configures the router to compare MEDs in choosing
the best path when paths have same AS-path
information.
no bgp deterministic-med
Configures the router not to compare MEDs even if the
paths have same AS-path.
