H3C Technologies H3C S12500 Series Switches - Manual (Page 214)

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Step Command Remarks
2. Associate Track with interface
management.
• Create a track entry, associate it with
the interface management module to
monitor the physical status of an
interface, and specify the delay time for
the Track module to notify the
associated application module when
the track entry status changes:
track track-entry-number interface
interface-type interface-number [ delay
{ negative negative-time | positive
positive-time } * ]
• Create a track entry, associate it with
the interface management module to
monitor the Layer 3 protocol status of
an interface, and specify the delay time
for the Track module to notify the
associated application module when
the track entry status changes:
track track-entry-number interface
interface-type interface-number
protocol { ipv4 | ipv6 } [ delay
{ negative negative-time | positive
positive-time } * ]
Use either method.
No track entry is created by
default.
Associating the Track module with an application
module
Associating Track with VRRP
VRRP is an error-tolerant protocol. It adds a group of routers that can act as network gateways to a VRRP
group, which forms a virtual router. Routers in the VRRP group elect the master acting as the gateway
according to their priorities. A router with a higher priority is more likely to become the master. The other
routers function as the backups. When the master fails, to make sure that the hosts in the network segment
can uninterruptedly communicate with external networks, the backups in the VRRP group elect a new
gateway to undertake the responsibility of the failed master.
When VRRP operates in standard protocol mode or load balancing mode, associate Track with the VRRP
group to implement the following actions:
• Change the priority of a router according to the status of the uplink. If a fault occurs on the uplink
of the router, the VRRP group cannot be aware of the uplink failure. If the router is the master, hosts
in the LAN cannot access the external network. This problem can be solved by establishing a
Track-VRRP group association. Use the detection modules to monitor the status of the uplink of the
router and establish collaborations between the detection modules, Track module and VRRP. When
the uplink fails, the detection modules notify the Track module to change the status of the monitored
track entry to Negative, and the priority of the master decreases by a specified value. This allows
a higher priority router in the VRRP group to become the master, and maintain proper
communication between the hosts in the LAN and the external network.