Juniper JUNOS OS 10.3 - SOFTWARE, Manual

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metric-out
Syntax metric-out (metric | minimum-igp offset | igp (delay-med-update | offset);
Hierarchy Level [edit logical-systems logical-system-name protocols bgp],
[edit logical-systems logical-system-name protocols bgp
group group-name],
[edit logical-systems logical-system-name protocols bgp group group-name neighbor address],
[edit logical-systems logical-system-name routing-instances routing-instance-name protocols
bgp],
[edit logical-systems logical-system-name routing-instances routing-instance-name protocols
bgp group group-name],
[edit logical-systems logical-system-name routing-instances routing-instance-name protocols
bgp group group-name neighbor address],
[edit protocols bgp],
[edit protocols bgp
group group-name],
[edit protocols bgp group group-name neighbor address],
[edit routing-instances routing-instance-name protocols bgp],
[edit routing-instances routing-instance-name protocols bgp
group group-name],
[edit routing-instances routing-instance-name protocols bgp group group-name
neighbor address]
Release Information Statement introduced before Junos OS Release 7.4.
Statement introduced in Junos OS Release 9.0 for EX Series switches.
delay-med-update option introduced in Junos OS Release 9.0.
Description Metric for all routes sent using the multiple exit discriminator (MED, or MULTI_EXIT_DISC )
path attribute in update messages. This path attribute is used to discriminate among
multiple exit points to a neighboring AS. If all other factors are equal, the exit point with
the lowest metric is preferred.
You can specify a constant metric value by including the
metric
option. For configurations
in which a BGP peer sends third-party next hops that require the local system to perform
next-hop resolution—IBGP configurations, configurations within confederation peers, or
EBGP configurations that include the
multihop command—you can specify a variable
metric by including the minimum-igp or igp option.
You can increase or decrease the variable metric calculated from the IGP metric (either
from the
igp
or
igp-minimum
statement) by specifying a value for
offset
. The metric is
increased by specifying a positive value for offset , and decreased by specifying a negative
value for offset .
In Junos OS Release 9.0 and later, you can specify for a BGP group or peer not to advertise
updates for the MED path attributes used to calculate IGP costs for BGP next hops unless
the MED is lower. You can also configure an interval to delay when MED updates are sent
by including the
med-igp-update-interval minutes at the [edit routing-options] hierarchy
level.
Options delay-med-update —Specify for a BGP group or peer configured with the metric-out igp
statement not to advertise MED updates when the value worsens, that is, unless the
value is lower.
1867 Copyright © 2010, Juniper Networks, Inc.
Chapter 73: Configuration Statements for Layer 3 Protocols