Vrrp Tracking; Configuring Collective Management Functionality; Interaction With Other Features; Vrrp Tracking With Bfd - Alcatel-Lucent OmniSwitch 9900 Series Network Configuration Manual

Configuring VRRP

VRRP Tracking

A virtual router's priority may be conditionally modified to prevent another router from taking over as
master. Tracking policies are used to conditionally modify the priority setting whenever a slot/port, IP
address and or IP interface associated with a virtual router goes down.
A tracking policy consists of a tracking ID, the value used to decrease the priority value, and the slot/port
number, IP address, or IP interface name to be monitored by the policy. The policy is then associated with
one or more virtual routers.

Configuring Collective Management Functionality

This feature provides user with the flexibility to manage the virtual routers on the switch collectively and
also the capability to group the virtual routers to a virtual router group which simplifies the configuration
and management tasks.
You can change the default values of the parameters like advertising interval, priority, preempt mode and
the administrative status of all the virtual routers on a switch or in a virtual router group using this
collective management functionality feature. For more information about configuring collective
management functionality, see
Note. VRRPv3 does not support the collective management functionality in this release.

Interaction With Other Features

•
IP routing—IP routing must be enabled for the VRRP configuration to take effect.
•
Router Discovery Protocol (RDP)—If RDP is enabled on the switch, and VRRP is enabled, RDP will
advertise VLAN IP addresses of virtual routers depending on whether there are virtual routers active on
the LAN, and whether those routers are backups or masters. When there are no virtual routers active on
the VLAN (either acting as master or backup), RDP will advertise all VLAN IP addresses. However, if
virtual routers are active, RDP will advertise IP addresses for any master routers; RDP will not
advertise IP addresses for backup routers.

VRRP Tracking with BFD

When VRRP tracking is used to monitor a remote IP address, the virtual router's priority adjusts based on
the reachability of the remote address. If the virtual router doing the tracking (the master) cannot reach the
remote address, the master gives up control and lets a router that can reach the remote address takeover.
Adding Bidirectional Forwarding Detection (BFD) into this scenario facilitates a quicker takeover by the
slave router than what would normally occur without BFD.
This interaction with BFD requires the slave router to have BFD enabled and a tracking policy for the
virtual router IP address with the priority value set to zero (so that the slave can become master). If the
priority value is set to non-zero, the tracking policy is treated normally and the priority of the slave is
reduced when the remote address becomes unreachable.
Note. Configuring the Loopback0 IP interface on the switch is required when enabling BFD for a remote
address tracking policy. The IP network address assigned to Loopback0 is used as the source IP address for
BFD packets.
OmniSwitch AOS Release 8 Network Configuration Guide
page 23-14.
December 2017
Interaction With Other Features
page 23-7