Dell C9000 series, Справочное руководство

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Version Description
9.9(0.0) Introduced on the C9010.
9.8(0.0) Introduced on the S3048-ON and S4048-ON.
9.7(0.0) Introduced on the S6000-ON.
8.3.12.0 Introduced on the S4810.
8.4.1.0 Introduced.
Usage Information Use this command to create an object that tracks the UP and/or DOWN threshold of an
IPv4 route metric. In order for a route’s metric to be tracked, the route must appear as
an entry in the routing table.
A tracked IPv4 route is considered to match an entry in the routing table only if the
exact IPv4 address and prefix length match a table entry. For example, when configured
as a tracked route, 10.0.0.0/24 does not match the routing table entry 10.0.0.0/8. If no
route-table entry has the exact IPv4 address and prefix length, the status of the tracked
route is considered to be DOWN.
When you configure the threshold of an IPv4 route metric as a tracked object, the UP/
DOWN state of the tracked route is also determined by the current metric for the route
in the routing table.
To provide a common tracking interface for different clients, route metrics are scaled in
the range 0 to 255, where 0 is connected and 255 is inaccessible. The scaled metric
value communicated to a client always considers a lower value to have priority over a
higher value. The resulting scaled value is compared against the configured threshold
values to determine the state of a tracked route as follows:
• If the scaled metric for a route entry is less than or equal to the UP threshold, the
state of a route is UP.
• If the scaled metric for a route is greater than or equal to the DOWN threshold or
the route is not entered in the routing table, the state of a route is DOWN.
You configure the UP and DOWN thresholds for each tracked route by using the
threshold metric
command. The default UP threshold is 254 ; the default DOWN
threshold is 255 . The notification of a change in the state of a tracked object is sent
when a metric value crosses a configured threshold.
Related
Commands
• show track – displays information about tracked objects, including configuration,
current state, and clients which track the object.
• threshold metric – configures the metric threshold used to determine the UP
and/or DOWN state of a tracked route.
• track resolution ip route – configures the protocol-specific resolution value used
to scale an IPv4 route metric.
Object Tracking 1469