Specifications

Chapter 6. IBM Virtual Fabric 10Gb Switch Module implementation 277
e. Configure preemption (Example 6-34).
Run [no] virtual-router <1-15> preemption to enable or disable master preemption.
When enabled, if this virtual router is in backup mode but has a higher priority than the
current Master, this virtual router pre-empts the lower priority Master and assumes
control. Even when preemption is disabled, this virtual router always preempts any
other Master if this switch is the owner (the IP interface address and virtual router addr
are the same). By default, this option is enabled.
Example 6-34 Configure preemption
AGG-1#configure terminal
Enter configuration commands, one per line. End with Ctrl/Z.
AGG-1(config)#router vrrp
AGG-1(config-vrrp)#virtual-router 3 preemption
AGG-1(config-vrrp)#
AGG-2#configure terminal
Enter configuration commands, one per line. End with Ctrl/Z.
AGG-2(config)#router vrrp
AGG-2(config-vrrp)#virtual-router 3 preemption
AGG-2(config-vrrp)#
f. Configure the timers, as shown in Example 6-35.
Run virtual-router <1-15> timers advertise <1-255> to define the time interval
between VRRP master advertisements. This value can be any integer 1 - 255 seconds.
The default value is 1.
Run virtual-router <1-15> timers preempt-delay-time <0-255> to configure the
preempt delay interval. This timer is configured on the VRRP Owner and prevents the
switch from moving back to the Master state until the preempt delay interval expires.
Ensure that the interval is long enough for OSPF or other routing protocols
to converge.
Run [no] virtual-router <1-128> fast-advertise to enable or disable Fast
Advertisements. When enabled, the VRRP master advertisements interval is
calculated in units of centiseconds, instead of seconds. For example, if adver is set to 1
and Fast Advertisement is enabled, master advertisements are sent every 0.01
second. When you disable fast advertisement, the advertisement interval is set to the
default value of 1 second. To support Fast Advertisements, set the interval to
20 - 100 centiseconds.
Example 6-35 Virtual router timers configuration
AGG-1#configure terminal
Enter configuration commands, one per line. End with Ctrl/Z.
AGG-1(config)#router vrrp
AGG-1(config-vrrp)#virtual-router 3 timers advertise 2
AGG-1(config-vrrp)#virtual-router 3 timers preempt-delay-time 5
AGG-1(config-vrrp)#
AGG-2#configure terminal
Enter configuration commands, one per line. End with Ctrl/Z.
AGG-2(config)#router vrrp
Important: Fast Advertisements were not used in reference architecture
implementation.