IBM Nortel Networks L2/3, Manual

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116
Nortel Networks L2/3 Ethernet Switch Module for IBM
Eserver
BladeCenter
Configuration of Hot-standby for VRRP
The commands in Example 7-24 add the hot-standby feature to the VRRP configuration.
Hot-standby is used in this sample with
interface tracking.
VRRP tracking allows a device to dynamically adjust its priority based on the availability of
other resources, and allow a standby switch to become master if the current master loses
access to those resources. Interface tracking counts the number of active IP interfaces and
increments the VRRP priority 2 units for each by default. The effect of use of interface
tracking in the sample configuration is to trigger VRRP failover and NIC teaming failover if
one of the uplink trunks connecting the master GbESM to the Core switches fails. Tracking
with hot-standby is applied to a VRRP
group
rather than to individual instances.
Note that a VLAN is created solely for the connection between the two switches. This is to
avoid triggering the hot-standby failover inappropriately. The same configuration is used for
both GbESM modules except where noted.
Example 7-24 VRRP Hot-standby configuration
/* create VLAN 50 and associated interface
/c/l2/vlan 50
ena
def ext3
/c/port ext3/pvid 50
/c/l3/if 50
addr 10.50.0.243
/* addr 10.50.0.244 for GbESM2
mask 255.255.255.0
vlan 50
ena
/* enable hot standby and VRRP group
/c/l3/vrrp/hotstan ena
/c/l3/vrrp/group
ena
if 50
prio 101
/* above only on GbESM1; defaults to 100 on GbESM 2
track
/* track ip interfaces on VLANs - they go down if no active ports are found
ifs ena
Configuration on Core switches to work with VRRP
The Core switches in this sample are not running VRRP. It is possible to develop a similar
configuration using VRRP or Cisco’s proprietary HSRP to allow the Core routers to present a
Note: The VRRP tracking features of the GbESM are very flexible and allow granular
control of when failover is triggered. There are many other possibilities besides what is
shown in this sample. Planning and testing of these features is essential.