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VRRP
VRRP is designed to eliminate the single point of failure inherent in the static default routed
environment. VRRP specifies an election protocol that dynamically assigns responsibility for a virtual
router to one of the VRRP routers in a LAN. The VRRP router controlling the IP address associated
with a virtual router is called the Master, and forwards packets sent to these IP addresses. The
election process provides dynamic fail-over in the forwarding responsibility should the Master
become unavailable. Any of the virtual router's IP addresses in a LAN can then be used as the
default first hop router by end-hosts. The advantage gained from using VRRP is a higher availability
default path without requiring configuration of dynamic routing or router discovery protocols on every
end-host.
VRRP:
Check Enable radio button to activate this function. The default setting is “Disable”.
VRID:
A master or backup router running the VRRP protocol may participate in one VRID instance.
Priority:
Specifies the sending VRRP router's priority for the virtual router. Higher values equal
higher priority. The priority value for the VRRP router that owns the IP address associated with the
virtual router MUST be 255. VRRP routers backing up a virtual router MUST use priority values
between 1 and 254. The default priority value for VRRP routers backing up a virtual router is 100.
The priority value zero (0) has special meaning indicating that the current Master has stopped
participating in VRRP. This is used to trigger Backup routers to quickly transition to Master without
having to wait for the current Master to timeout.
Preempt Mode:
When preempt mode is enabled, a backup router always takes over the
responsibility of the master router. When disabled, the lower priority backup is left in the master state.
VRIP:
One IP address that is associated with the virtual router.
Advertisement period:
Indicates the time interval in seconds between advertisements. The default
value is 1 second.