Modifying load balancing and failover

About load balancing

Load balancing enables incoming and outgoing traffic to be spread across ATM adapters in a group.

By default, all ATM adapters are dynamically assigned to load-balancing groups. In this case, no configuration is necessary to activate the load balancing and failover features. However, you can override the default by changing the adapters to static mode so groups can be manually configured, for instance, when a failover group contains adapters on different switches, resulting in reduced network performance.

Requirements for load balancing

Load balancing does not depend on any nonstandard extensions to the UNI. However, the switch must support the following:

Registering the same ATM address on multiple ports
Registering multiple ATM addresses on a single port

If the switch does not support these features, load balancing and failover are automatically disabled.

Modifying load balancing groups

To modify load-balancing groups, complete the following step.

Step	Action
1	Enter the following command: atm uniconfig set failover [ -state off \| static \| dynamic ] [-group unit ... ] `-state dynamic` is the default. Use `-state off` to disable load balancing and failover, `-state static` to put UNI load-balancing in a static mode, and `-group unit...` to specify the load-balancing group membership. Note The parameters to the `-group` option of the `atm uniconfig set failover` command specify the ATM adapters (units) that should be logically assigned to a load-balancing and failover group. If you specify a unit that has already been assigned to another group, the unit is automatically removed from the original group before being assigned to the new group.

Step

Action

Enter the following command:

atm uniconfig set failover [ -state off | static | 
dynamic ] [-group unit ... ]

-state dynamic is the default.

Use -state off to disable load balancing and failover, -state static to put UNI load-balancing in a static mode, and -group unit... to specify the load-balancing group membership.

Note
The parameters to the -group option of the atm uniconfig set failover command specify the ATM adapters (units) that should be logically assigned to a load-balancing and failover group. If you specify a unit that has already been assigned to another group, the unit is automatically removed from the original group before being assigned to the new group.

Example of the atm uniconfig set failover command

The following example demonstrates how you disable load balancing and failover:

atm uniconfig set failover -state off