DELL 9.8(0.0) User Manual

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track ip route reachability
Configure object tracking on the reachability of an IPv4 route.
Syntax
track object-id ip route ip-address/prefix-len reachability 
[vrf vrf-name]
To return to the default setting, use the no track object-id command.
Parameters
object-id
Enter the ID number of the tracked object. The range is 1 to 
500.
ip-address/ 
prefix-len
Enter an IPv4 address in dotted decimal format. The valid 
IPv4 prefix lengths are from /0 to /32.
vrf vrf-name
(Optional) E-Series only: You can configure a VPN routing 
and forwarding (VRF) instance to specify the virtual routing 
table to which the tracked route belongs.
Defaults
none
Command 
Modes
CONFIGURATION
Command 
History
Version
Description
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 reachability of an IPv4 route. 
In order for a route’s reachability 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 IPv4 route reachability as a tracked object, the UP/DOWN 
state of the tracked route is also determined by the entry of the next-hop address 
in the ARP cache. A tracked route is considered to be reachable if there is an ARP 
cache entry for the route's next-hop address.
If the next-hop address in the ARP cache ages out for a route tracked for its 
reachability, an attempt is made to regenerate the ARP cache entry to if the next-
hop address appears before considering the route DOWN.
Object Tracking
1251