H3C Technologies H3C S12500 Series Switches - Manual (Page 155)

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Step Command Remarks
1. Enter system view. system-view N/A
2. Enter interface view.
interface interface-type
interface-number
N/A
3. Configure router priority in the
VRRP group. vrrp vrid virtual-router-id priority
priority-value Optional.
100 by default.
4. Configure the router in the
VRRP group to operate in
preemptive mode and
configure preemption delay.
vrrp vrid virtual-router-id
preempt-mode [ timer delay
delay-value ]
Optional.
The router in the VRRP group
operates in preemptive mode and
the preemption delay is 0 seconds
by default.
5. Configure the interface to be
tracked.
vrrp vrid virtual-router-id track
interface interface-type
interface-number [ reduced
priority-reduced ]
Optional.
No interface is being tracked by
default.
6. Configure VRRP to track a
specified track entry.
vrrp vrid virtual-router-id track
track-entry-number [ reduced
priority-reduced | switchover ]
Optional.
Not configured by default.
Configuring VF tracking
Configuration prerequisites
Before you configure the VF tracking function, create a VRRP group and configure a virtual IP address for
it.
Configuration guidelines
When you configure VF tracking, follow these guidelines:
• You can configure the VF tracking function when VRRP is operating in either standard protocol
mode or load balancing mode. However, the VF tracking function is effective only when VRRP is
operating in load balancing mode.
• By default, the weight of a VF is 255, and its lower limit of failure is 10.
• If the weight of a VF owner is higher than or equal to the lower limit of failure, the priority of the VF
owner is always 255 and does not change with the weight value. Therefore, in case of an uplink
failure, another VF takes over the VF owner's work and becomes the AVF only when the weight of
the VF owner decreases by a correctly specified value and becomes lower than the lower limit of
failure. In other words, the weight of the VF owner decreases by more than 245.
Configuration procedure
Assume that VRRP is operating in load balancing mode, and you have configured the VF tracking
function to monitor the track entry and specified the value by which the weight decreases. When the
status of the track entry becomes negative, the weight values of all VFs on the router decrease by the
specified value. When the status of the track entry becomes positive or invalid, the weight values of all
VFs on the router restore their original values.
If you configure the VF tracking function on an LVF to monitor its corresponding AVF on a specified router,
the LVF can take over the AVF immediately when the status of the track entry becomes negative, to ensure
uninterrupted network communications.