Vrrp Overview; Vrrp Components; Virtual Router; Virtual Router Mac Address - Lenovo RackSwitch G8264 Application Manual

VRRP Overview

VRRP Components

Virtual Router

Virtual Router MAC Address

Owners and Renters

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G8264 Application Guide for ENOS 8.4
In a high‐availability network topology, no device can create a single
point‐of‐failure for the network or force a single point‐of‐failure to any other part
of the network. This means that your network will remain in service despite the
failure of any single device. To achieve this usually requires redundancy for all
vital network components.
VRRP enables redundant router configurations within a LAN, providing alternate
router paths for a host to eliminate single points‐of‐failure within a network. Each
participating VRRP‐capable routing device is configured with the same virtual
router IPv4 address and ID number. One of the virtual routers is elected as the
master, based on a number of priority criteria, and assumes control of the shared
virtual router IPv4 address. If the master fails, one of the backup virtual routers
will take control of the virtual router IPv4 address and actively process traffic
addressed to it.
With VRRP, Virtual Interface Routers (VIR) allow two VRRP routers to share an IP
interface across the routers. VIRs provide a single Destination IPv4 (DIP) address
for upstream routers to reach various servers, and provide a virtual default
Gateway for the servers.
Each physical router running VRRP is known as a VRRP router.
Two or more VRRP routers can be configured to form a virtual router (RFC 2338).
Each VRRP router may participate in one or more virtual routers. Each virtual
router consists of a user‐configured virtual router identifier (VRID) and an IPv4
address.
The VRID is used to build the virtual router MAC Address. The five highest‐order
octets of the virtual router MAC Address are the standard MAC prefix
(00‐00‐5E‐00‐01) defined in RFC 2338. The VRID is used to form the lowest‐order
octet.
Only one of the VRRP routers in a virtual router may be configured as the IPv4
address owner. This router has the virtual router's IPv4 address as its real interface
address. This router responds to packets addressed to the virtual router's IPv4
address for ICMP pings, TCP connections, and so on.
There is no requirement for any VRRP router to be the IPv4 address owner. Most
VRRP installations choose not to implement an IPv4 address owner. For the
purposes of this chapter, VRRP routers that are not the IPv4 address owner are
called renters.