HP Auto Port Aggregation Administrator's Guide HP-UX 11i v3 (766140-001, March 2014)

Example 2
You want to configure a failover group (lan902) for proactive failover. You decide that the failover
group consists of two link aggregates: lan900 and lan901. The lan900 aggregate consists of
ports 2 and 3; the lan901 aggregate consists of ports 4 and 5. Ports 2, 3, 4, and 5 have speeds
of 100 Mb/s. In addition, the link aggregates are connected to different routers using different
speeds to connect to the network.
To configure the failover group for proactive failover, do the following:
1. Determine network efficiency.
In this example, you determine that the router connected to lan900 is 1.5 times more efficient
at delivering traffic to the network than the router connected to lan901. You assign lan900
a cost of 1 and lan901 a cost of 1.5. However, you must express cost values in the
lanconfig.ascii file using whole numbers (no decimal points). The ratio of 1 to 1.5 is
the same as the ratio of 2 to 3. Therefore, lan900 has a cost of 2 and lan901 has a cost
of 3.
2. Assign a priority to the aggregates.
Because you prefer lan900 over lan901, you assign lan900 a priority of 8 and lan901
a priority of 7. That way, if both ports have the same normalized port cost, lan900 has
precedence over lan901.
3. Edit the configuration file.
FAILOVER_GROUP lan902
STATIONARY_IP 10.0.1.60
# Primary/Standby Interface Priority : Cost
# –––––––––––––––––––––––+–––––––––––––+––––––––––––––––
PRIMARY lan900 8 : 2
STANDBY lan901 7 : 3
Table 3 lists lan900 events for this example and how proactive failover determines the active port
for lan902.
Table 3 lan900 Events and Proactive Failover (Unequal Network Costs)
Active Portlan901 Normalized Port Costlan900 Normalized Port CostEvent
lan900
2
3/200, or .0152/200, or .010Failover group constructed
1
lan901
3
3/200, or .0152/100, or .020Port 2 on lan900 is
DOWN
lan900
4
3/200, or .0152/200, or .010Port 2 on lan900 is UP
lan900
5
3/100, or .0302/200, or .010Port 4 on lan901 is
DOWN
lan900
6
3/200, or .0152/200, or .010Port 4 on lan901 is UP
lan901
7
3/200, or .0150Ports 2 and 3 on lan900
are DOWN
1
All ports in the link aggregates are operational.
2
Normalized port cost is lower than lan901.
3
Normalized port cost is lower than lan900.
4
Normalized port cost is lower than lan901.
5
Normalized port cost is lower than lan901.
6
Normalized port cost is lower than lan901.
7
This behavior is the same as if lan902 were a priority-based failover group.
Editing configuration files for link aggregates 91