Users Guide

414 | VRRP Dell PowerConnect ArubaOS 5.0 | [User Guide
Configuring the Local Controller for Redundancy
In an Dell network, the APs are controlled by a controller. The APs tunnel all data to the controller which
processes the data, including encryption/decryption, bridging/forwarding, etc.
Local controller redundancy refers to providing redundancy for a controller such that the APs “fail over” to a
backup controller if a controller becomes unavailable. Local controller redundancy is provided by running VRRP
between a pair of controllers.
The APs are then configured to connect to the “virtual-IP” configured for the VRRP instance.
Collect the following information needed to configure local controller redundancy:
z VLAN ID on the two local controllers that are on the same Layer-2 network and is used to configure VRRP.
z Virtual IP address to be used for the VRRP instance.
You can use either the WebUI or CLI to configure VRRP on the local controllers. For this topology, it is
recommended to use the default priority value.
In the WebUI
1. Navigate to the Configuration > Advanced Services > Redundancy page on the WebUI for each of the local
controllers.
2. Under Virtual Router Table, click Add to create a VRRP instance.
3. Enter the IP Address for the virtual router. Select the VLAN on which VRRP will run. Set the Admin State to
Up.
Tracking Configures a tracking mechanism that modifies a specified value to the priority after a
controller has been the master for the VRRP instance. This mechanism is used to avoid failing
over to a backup Master for transient failures.
Tracking can be based on one of the following:
z Master Up Time: how long the controller has been the master. The value of duration is the
length of time that the administrator expects will be long enough that the database
gathered in the time is too important to be lost. This will obviously vary from instance to
instance.
z VRRP Master State Priority: the master state of another VRRP.
Tracking can also be based on the interface states of the controller:
z VLAN and Interface: prevents asymmetric routing by tracking multiple VRRP instances.
The priority of the VRRP interface determined by the sub value can increase or decrease
based on the operational and transitional states of the specified VLAN or Fast Ethernet/
Gigabit Ethernet port. When the VLAN or interface comes up again, the value is restored
to the previous priority level. You can track a combined maximum of 16 interfaces and
VLANs.
For example, you can track an interface that connects to a default gateway. In this situation,
configure the VRRP priority to decrease and trigger a VRRP master re-election if the interface
goes down. This not only prevents network traffic from being forwarded, but reduces VRRP
processing.
Admin State Administrative state of the VRRP instance. To start the VRRP instance, change the admin state
to UP in the WebUI.
VLAN VLAN on which the VRRP protocol will run.
Table 82 VRRP Parameters (Continued)
Parameter Description
Note: The two controllers need to be connected on the same broadcast domain (or Layer-2 connected) for VRRP operation. The
two controllers should be of the same class (for example, A800 to A800 or higher), and both controllers should be running the same
version of ArubaOS.