Redundancy (Vrrp) Configuration - NetComm NTC-220 User Manual

Redundancy (VRRP) configuration

Virtual Router Redundancy Protocol (VRRP) is a non-proprietary redundancy protocol designed to increase the
availability of the default gateway servicing hosts on the same subnet. This increased reliability is achieved by
advertising a "virtual router" (an abstract representation of master and backup routers acting as a group) as a
default gateway to the host(s) instead of one physical router. Two or more physical routers are then configured to
stand for the virtual router, with only one doing the actual routing at any given time. If the current physical router
that is routing the data on behalf of the virtual router fails, an arrangement is made for another physical router to
automatically replace it. The physical router that is currently forwarding data on behalf of the virtual router is called
the master router. Routers are given a priority of between 1 and 255 and the router with the highest priority is
assigned as the master.
A virtual router must use 00-00-5E-00-01-XX as its (MAC) address. The last byte of the address (XX) is the Virtual
Router Identifier (VRID), which is different for each virtual router in the network. This address is used by only one
physical router at a time and is the only way that other physical routers can identify the master router within a virtual
router.
To access the Redundancy (VRRP) page, click on the Networking menu at the top of the screen, click on the
Routing menu on the left, then click on the Redundancy (VRRP) menu item.
To configure VRRP, configure multiple devices as follows and connect them all via an Ethernet network switch to
downstream devices.
1 Click the Redundancy (VRRP) toggle key to ON in order to activate VRRP.
2 In the Virtual ID field, enter an ID between 1 and 255. This is the VRRP ID which is different for each virtual
router on the network.
3 In the Router priority field, enter a value for the priority – a higher value is a higher priority.
4 The Virtual IP address field is used to specify the VRRP IP address – this is the virtual IP address that both
virtual routers share.
5 Click the Save button to save the new settings.
Note – Configuring VRRP changes the MAC address of the Ethernet port and therefore if you want to resume with the web configuration
you must use the new IP address (VRRP IP) or clear the arp cache (old MAC address) on a command prompt by typing:
arp –d <ip address> (i.e. arp –d 192.168.1.1)
NTC-220 – User Guide
UG01028 v1.2 March 2019
Figure 65 – VRRP configuration
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© NetComm Wireless 2019