R3303-HP HSR6800 Routers High Availability Configuration Guide

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Configuration procedure
VRRP operates in load balancing mode. Assume that 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.
You can configure the VF tracking function when VRRP operates in either standard mode or load
balancing mode. However, the VF tracking function is effective only when VRRP operates 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.
To configure VF tracking:
Ste
p
Command Remarks
1. Enter system view.
system-view N/A
2. Enter the specified interface
view.
interface interface-type
interface-number
N/A
3. Configure VF tracking.
• Configure the VF tracking
function to monitor a specified
track entry and specify the
value by which the weight
decreases:
vrrp vrid virtual-router-id weight
track track-entry-number
[ reduced weight-reduced ]
• Configure the VF tracking
function to monitor an AVF on a
specified router:
vrrp vrid virtual-router-id track
track-entry-number
forwarder-switchover
member-ip ip-address
Use either method.
The VF tracking function is not
configured by default.
Enabling ARP entry backup
After a master/backup switchover occurs in a VRRP group, the new master might need to learn ARP
entries of the hosts on the LAN, causing traffic interruption.
The ARP entry backup function enables the master to send the dynamic ARP entries of hosts through VRRP
advertisements to other VRRP group members. In this way, when a master/backup switchover occurs, the
new master does not need to learn the ARP entries again.