Changing The Timer Scale - Brocade Communications Systems FastIron SX 800 Configuration Manual

To disable preemption on a Backup, enter commands such as the following.
device Router1(config)#interface ethernet 1/1/6
device Router1(config-if-1/1/6)#ip vrrp vrid 1
device Router1(config-if-1/1/6-vrid-1)#non-preempt-mode
Syntax: [no] non-preempt-mode
The syntax is the same for VRRP and VRRP-E.

Changing the timer scale

NOTE
Changing the timer scale is supported for IPv4 VRRP v2, IPv4 VRRP-E v2, and IPv6 VRRP-E v3. It is not supported for IPv6
VRRP v3.
To achieve sub-second failover times, you can shorten the duration of all scale timers for VSRP, VRRP, and VRRP-E by adjusting the
timer scale. The timerscale is a value used by the software to calculate the timers. By default, the scale value is 1. If you increase the
timer scale, each timer's value is divided by the scale value. Using the timer scale to adjust timer values enables you to easily change all
the timers while preserving the ratios among their values.
TABLE 104 Time scale values
Timer
Hello interval
Dead interval
Backup Hello interval
Hold-down interval
If you configure the device to receive its timer values from the Master, the Backup also receives the timer scale value from the Master.
To change the timer scale, enter a command such as the following at the global CONFIG level of the CLI.
device(config)# scale-timer 2
This command changes the scale to 2. All VSRP, VRRP, and VRRP-E timer values will be divided by 2.
Syntax: [no] scale-timer num
The num variable specifies the multiplier. You can specify a timer scale from 1 through 10. However, Brocade recommends the timer
scale of 1 or 2 for VRRP and VRRP-E.
NOTE
Be cautious when configuring the scale-timer command in a VRRP or VRRP-E scaled environment. VSRP, VRRP, and VRRP-
E are time-sensitive protocols and system behavior cannot be predicted when the timers are scaled.
FastIron Ethernet Switch Layer 3 Routing
53-1003627-04
Timer scale
1
2
1
2
1
2
1
2
Additional VRRP and VRRP-E parameter configuration
Timer value
1 second
0.5 seconds
3 seconds
1.5 seconds
60 seconds
30 seconds
2 seconds
1 second
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