Filter
Top Products
Nokia Network Voyager for IPSO 4.0 Reference Guide 187
Use this method only if you do not have an extra IP address to use for monitored-circuit
VRRP. For more information see “Configuring VRRPv2”.
Selecting Configuration Parameters
Before you begin, plan your implementation by deciding how you want to set the following
configuration parameters.
Priority
Hello Interval
Authentication
Priority Delta
Backup Address
VMAC Mode
Priority
The priority value determines which router takes over in the event of a failure; the router with
the higher priority becomes the new master. The range of values for priority is 1 to 254. The
default setting is 100.
Note
In Nokia’s monitored-circuit VRRP, the master is defined as the router with the highest
priority setting, although RFC 3768 specifies that the master must have a priority setting of
255.
If two platforms have equivalent priorities, the platform that comes online and starts
broadcasting VRRP advertisements first becomes the master. If there is a tie, the platform with
the higher IP address is selected.
To prevent the unlikely event that the tie-breaking algorithm selects one platform as the master
for the external network and another as the master router for the internal network, you should
make all interfaces on one platform numerically greater than the interfaces on the peer. For
example, Platform A should be the .1 host and Platform B should be the .2 host on all connected
interfaces.
You should set the priority to 254 for least the master platform in each VRID to provide a faster
transition in the event of a failure. Using higher values can decrease the time it takes for a
backup router to take over for a failed router by close to one second.
Note
Setting a higher priority shortens the transition time because the time interval for a backup to
declare the master down is calculated as
Master_Down_Interval = (3 * Hello_interval) + Skew_time; and the skew time (seconds by