Vrrp Benefits; Multiple Vrrp Groups - Cisco Nexus 3000 Series Configuration Manual

Chapter 13 Configuring VRRP
S e n d d o c u m e n t c o m m e n t s t o n e x u s 3 k - d o c f e e d b a c k @ c i s c o . c o m
Routers B and C function as backups. If the master fails, the backup router with the highest priority
becomes the master and takes over the virtual IP address to provide uninterrupted service for the LAN
hosts. When router A recovers, it becomes the r master again. For more information, see the
Router Priority and Preemption"
Packets received on a routed port destined for the VRRP virtual IP address will terminate on the local
Note
router, regardless of whether that router is the master VRRP router or a backup VRRP router. This
includes ping and telnet traffic. Packets received on a Layer 2 (VLAN) interface destined for the VRRP
virtual IP address will terminate on the master router.

VRRP Benefits

The benefits of VRRP are as follows:
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Multiple VRRP Groups

You can configure up to 255 VRRP groups on a physical interface. The actual number of VRRP groups
that a router interface can support depends on the following factors:
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In a topology where multiple VRRP groups are configured on a router interface, the interface can act as
a master for one VRRP group and as a backup for one or more other VRRP groups.
Figure 13-2
traffic to and from clients 1 through 4. Routers A and B act as backups to each other if either router fails.
Redundancy–Enables you to configure multiple routers as the default gateway router, which reduces
the possibility of a single point of failure in a network.
Load Sharing–Allows traffic to and from LAN clients to be shared by multiple routers. The traffic
load is shared more equitably among available routers.
Multiple VRRP groups–Supports up to 255 VRRP groups on a router physical interface if the
platform supports multiple MAC addresses. Multiple VRRP groups enable you to implement
redundancy and load sharing in your LAN topology.
Multiple IP Addresses–Allows you to manage multiple IP addresses, including secondary IP
addresses. If you have multiple subnets configured on an Ethernet interface, you can configure
VRRP on each subnet.
Preemption–Enables you to preempt a backup router that has taken over for a failing master with a
higher priority backup router that has become available.
Advertisement Protocol–Uses a dedicated Internet Assigned Numbers Authority (IANA) standard
multicast address (224.0.0.18) for VRRP advertisements. This addressing scheme minimizes the
number of routers that must service the multicasts and allows test equipment to accurately identify
VRRP packets on a segment. IANA has assigned the IP protocol number 112 to VRRP.
VRRP Tracking–Ensures that the best VRRP router is the master for the group by altering VRRP
priorities based on interface states.
Router processing capability
Router memory capability
shows a LAN topology in which VRRP is configured so that Routers A and B share the
Cisco Nexus 3000 Series NX-OS Unicast Routing Configuration Guide, NX-OS Release 5.0(3)U1(1)
section.
Information About VRRP
"VRRP
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