Dell Force10 Z9000 Configuration Manual page 803

NOTE: You must configure all virtual routers in the VRRP group the same: you must configure all with preempt enabled or
configure all with preempt disabled.
Because preempt is enabled by default, disable the preempt function with the following command.
• Prevent any BACKUP router with a higher priority from becoming the MASTER router.
INTERFACE-VRID mode
no preempt
Examples of Disabling Preempt
Re-enable preempt by entering the preempt command. When you enable preempt, it does not display in the show commands,
because it is a default setting.
The following example shows how to disable preempt using the no preempt command.
Dell(conf-if-te-1/1)#vrrp-group 111
Dell(conf-if-te-1/1-vrid-111)#no preempt
Dell(conf-if-te-1/1-vrid-111)#
The following example shows how to verify preempt is disabled using the show conf command.
Dell(conf-if-te-1/1-vrid-111)#show conf
!
vrrp-group 111
authentication-type simple 7 387a7f2df5969da4
no preempt
priority 255
virtual-address 10.10.10.1
virtual-address 10.10.10.2
virtual-address 10.10.10.3
virtual-address 10.10.10.10
Changing the Advertisement Interval
By default, the MASTER router transmits a VRRP advertisement to all members of the VRRP group every one second, indicating it is
operational and is the MASTER router.
If the VRRP group misses three consecutive advertisements, the election process begins and the BACKUP virtual router with the
highest priority transitions to MASTER.
NOTE: To avoid throttling VRRP advertisement packets, Dell Networking OS recommends increasing the VRRP
advertisement interval to a value higher than the default value of one second. If you do change the time interval between
VRRP advertisements on one router, change it on all participating routers.
If are using VRRP version 2, you must configure the timer values in multiple of whole seconds. For example a timer value of 3
seconds or 300 centisecs are valid and equivalent. However, a time value of 50 centisecs is invalid because it not a multiple of 1
second. If you are using VRRP version 3, you must configure the timer values in multiples of 25 centisecs.
If you are configured for VRRP version 2, the timer values must be in multiples of whole seconds. For example, timer value of 3
seconds or 300 centisecs are valid and equivalent. However, a timer value of 50 centisecs is invalid because it not is not multiple of
1 second.
If are using VRRP version 3, you must configure the timer values in multiples of 25 centisecs.
To change the advertisement interval in seconds or centisecs, use the following command. A centisecs is 1/100 of a second.
• Change the advertisement interval setting.
INTERFACE-VRID mode
advertise-interval seconds
The range is from 1 to 255 seconds.
The default is 1 second.
Virtual Router Redundancy Protocol (VRRP)
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