418 BigIron RX Series Configuration Guide53-1001810-01Configuring basic VSRP parameters15 MAC address failover on VSRP-aware devicesVSRP-aware devices maintain a record of each VRID and its VLAN. When the device has received aHello message for a VRID in a given VLAN, the device creates a record for that VRID and VLAN andincludes the port number in the record. Each subsequent time the device receives a Hellomessage for the same VRID and VLAN, the device checks the port number:• If the port number is the same as the port that previously received a Hello message, theVSRP-aware device assumes that the message came from the same VSRP Master that sentthe previous message.• If the port number does not match, the VSRP-aware device assumes that a VSRP failover hasoccurred to a new Master, and moves the MAC addresses learned on the previous port to thenew port.The VRID records age out if unused. This can occur if the VSRP-aware device becomesdisconnected from the Master. The VSRP-aware device will wait for a Hello message for the periodof time equal to the following.VRID Age = (Dead Interval + Hold-down Interval + (3 x Hello Interval))/10The values for these timers are determined by the VSRP device sending the Hello messages. If theMaster uses the default timer values, the age time for VRID records on the VSRP-aware devices isas follows.3 + 3 + (3 x 1)/10 = .9 seconds(900 milliseconds)In this case, if the VSRP-aware device does not receive a new Hello message for a VRID in a givenVLAN, on any port, the device assumes the connection to the Master is unavailable and removesthe VRID record.Configuring basic VSRP parametersTo configure VSRP, perform the following required tasks.1. Configure a port-based VLAN containing the ports for which you want to provide VSRP service.NOTEIf you already have a port-based VLAN but only want to use VSRP on a sub-set of the VLANsports, you can selectively remove ports from VSRP service in the VLAN. Refer to “Adding orremoving a port from the VRID’s VLAN” on page 420.BigIron RX(config)# vlan 200BigIron RX(config-vlan-200)# tag ethernet 1/1 to 1/82. Configure a VRID.BigIron RX(config-vlan-200)# vsrp vrid 1Syntax: [no] vsrp vrid The parameter specifies the VRID and can be from 1 – 255.3. Specify that the device is a backup. Since VSRP, like VRRPE, does not have an “owner”, allVSRP devices are backups. The active device for a VRID is elected based on the VRID priority,which is configurable.BigIron RX(config-vlan-200-vrid-1)# backup
