Specifications

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Cisco Nexus 3000 Series NX-OS Unicast Routing Configuration Guide, Release 5.0(3)U2(2)
OL-25782-02
Chapter 15 Configuring VRRP
Information About VRRP
VRRP Advertisements
The VRRP master sends VRRP advertisements to other VRRP routers in the same group. The
advertisements communicate the priority and state of the master. Cisco NX-OS encapsulates the VRRP
advertisements in IP packets and sends them to the IP multicast address assigned to the VRRP group.
Cisco NX-OS sends the advertisements once every second by default, but you can configure a different
advertisement interval.
VRRP Authentication
VRRP supports the following authentication mechanisms:
• No authentication
• Plain text authentication
VRRP rejects packets in any of the following cases:
• The authentication schemes differ on the router and in the incoming packet.
• Text authentication strings differ on the router and in the incoming packet.
VRRP Tracking
VRRP supports the following two options for tracking:
• Native interface tracking— Tracks the state of an interface and use that state to determine the
priority of the VRRP router in a VRRP group. The tracked state is down if the interface is down or
if the interface does not have a primary IP address.
• Object tracking—Tracks the state of a configured object and use that state to determine the priority
of the VRRP router in a VRRP group. See Chapter 16, “Configuring Object Tracking” for more
information on object tracking.
If the tracked state (interface or object) goes down, VRRP updates the priority based on what you
configure the new priority to be for the tracked state. When the tracked state comes up, VRRP restores
the original priority for the virtual router group.
For example, you may want to lower the priority of a VRRP group member if its uplink to the network
goes down so another group member can take over as master for the VRRP group. See the “Configuring
VRRP Interface State Tracking” section on page 15-15 for more information.
Note VRRP does not support Layer 2 interface tracking.
Virtualization Support
VRRP supports Virtual Routing and Forwarding instances (VRFs). By default, Cisco NX-OS places you
in the default VRF unless you specifically configure another VRF.
If you change the VRF membership of an interface, Cisco NX-OS removes all Layer 3 configuration,
including VRRP.
For more information, see Chapter 11, “Configuring Layer 3 Virtualization.”