Vrrp Timer; Vrrp Tracking - 3Com 5500-EI PWR Install Manual

You need to configure the mapping between the IP addresses of the VRRP group and the MAC
address before enabling VRRP feature on a 5500-EI Ethernet switch. If VRRP is already enabled,
the system does not support this configuration.
The number of virtual router IP addresses that can be mapped with the virtual router MAC address
is determined by the chips of the switches in the VRRP group.
A switch can belong to multiple VRRP groups. However, the number of VRRP groups supported by
a switch is determined by the chip it uses. Refer to device specification for details.

VRRP Timer

There are two types of VRRP timer, the VRRP advertisement interval timer and the VRRP preemption
delay timer.
VRRP advertisement interval timer
The master advertises its normal operation state to the switches within the VRRP group by sending
VRRP packets once in each specified interval (determined by the adver-interval argument).
You can adjust the interval for a master to send VRRP advertisements by setting the VRRP
advertisement interval timer. If a backup does not receive the VRRP advertisements from the
master after a period three times of the specified interval, it considers itself as the master and
sends out VRRP advertisements to reelect the master.
VRRP preemption delay timer
The backup may not receive a VRRP advertisement within a period three times of the specified
interval due to excessive network traffic or network instability. In this case, you can configure the
VRRP preemption delay for backups.
If you configure the preemption delay for a backup, the switch preempts the master if it does not
receive a VRRP advertisement from the master after it waits for a period three times of the
advertisement interval and the period specified by the preemption delay.

VRRP Tracking

If an IP address owner exists in a VRRP group, you can configure a priority for the IP address
owner. However your configuration will not take effect and the IP address owner will still be the
master of the VRRP group because the system considers the priority of the IP address owner to be
255 always.
If an IP address owner exists in a VRRP group, the interface/port tracking function configured on
the IP address owner cannot take effect.
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