Vrrp Operation In The Network; Vrrp Router Priority; Vrrp Preemption - Fujitsu PSWITCH 2048T User Manual

User's Guide FUJITSU PSWITCH
the default router (L3 switch) by dynamically selecting the backup router. VRRP
helps to minimize black hole period during which all traffic is lost until the failure is
detected after the default gateway router fails.

3.1.9.17.1. VRRP Operation in the Network

VRRP takes over from the master router the backup router without affecting the
end stations using the route and eliminates a single point of failure for the static
default route. If the master router fails, the end station uses the virtual IP address
recognized by the backup router.
Participating routers use the election protocol to determine which router is the
master router at any given time. A port may be configured as multiple virtual
routers on the network. Also, multiple ports on the switch may be configured as
virtual routers. Either physical port or VLAN can participate.
In VRRP, a virtual router is associated with one or more IP addresses that serve as
the default gateway. If a VRRP master router that controls these IP addresses fails,
the group of IP addresses and the default forwarding role are handed over to the
backup VRRP router.

3.1.9.17.2. VRRP Router Priority

The VRRP router priority is a value between 1 and 255, which determines which
router is the master. The higher the number, the higher the priority. If the virtual IP
address is the IP address of the VLAN routing interface on one of the routers in the
VRRP group, the router with the same IP address as the virtual IP address is the
interface owner and the priority is 255. By default, this router is a VRRP master in
the group. If the router in the group does not own the VRRP virtual IP address, the
router with the highest priority becomes the VRRP master. If multiple routers have
the same priority, the router with the highest IP address becomes the VRRP master.
When a VRRP master fails, the other members of the VRRP group elect a master
based on the configured router priority. For example, router A is the owner and
master of the interface and assumes a priority of 255. Router B has priority set to
200 and router C has priority set to 190. If router A fails, router B with the higher
priority takes the role of VRRP master.

3.1.9.17.3. VRRP Preemption

When preemption mode is enabled and a high priority router joins the VRRP group,
if the current VRRP master is not the owner of the virtual IP address, that new
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