Enhanced Load Sharing Groups CapacityNEW!

Platform Capacity

The maximum number of load sharing groups varies by platform capability:

• 512 LAGs: High-capacity Universal Platforms (7520, 7720 series)
• 128 LAGs: All other platforms

The general rule of 8 ports per LAG applies to all platforms regardless of the maximum LAG count. These limits apply to both standalone switches and stack configurations.

Configuring Load Sharing Groups

The syntax for creating and managing load sharing groups remains unchanged. The enhanced capacity is available automatically on supported platforms:

enable sharing <port> grouping <port_list> {algorithm [address-based {L2 | L3 | L3_L4 | custom}]}

Example creating a load sharing group:

enable sharing 1 grouping 1-4 algorithm address-based L3_L4

Stack Considerations

In stack configurations with mixed platform capacities, the system intelligently manages LAG limits to ensure stable operation.

Mixed-Capacity Stack Behavior:

When a node with lower LAG capacity joins a stack where the active LAG count exceeds its supported limit:

• The new node's ports remain disabled to prevent network flooding
• An EMS warning message indicates the LAG capacity mismatch and the number of LAGs that must be removed
• The stack continues to operate with the existing LAGs on nodes that support the current count

Resolving Capacity Mismatches:

To restore full stack operation when a capacity mismatch occurs, choose one of the following approaches:

1. Reduce LAG count: Remove LAGs until the total is at or below the lowest capacity in the stack. The new node's ports will become operational once the LAG count is reduced.
2. Reconfigure stack topology: Use the reboot stacktopology command to reinitialize the stack. This clears all LAG configurations and allows you to rebuild your configuration within the new limits.

Port Addition Restrictions:

The system prevents adding ports from lower-capacity nodes to LAGs when the total number of configured LAGs exceeds that node's limit. When attempting to add such ports, an error message indicates the capacity restriction and the number of LAGs that must be removed before the operation can succeed.

Example error message:

Cannot add port 2:5 to Load Share Group. Slot 2 supports only 128 Load Share Groups 
but system has 256 Load Share Groups configured. Reduce Load Share Groups to 128 or 
fewer before adding ports from this slot.

Best Practices

• When building stacks, use platforms with similar LAG capacity to avoid operational restrictions
• Document your LAG configuration before adding nodes with different capacities to a stack
• Monitor EMS messages when adding new nodes to stacks with high LAG counts
• Plan LAG deployment to stay within the limits of the lowest-capacity platform in your stack

Viewing Load Sharing Group Information

Use the show sharing command to display current load sharing group configuration and port membership. The system does not explicitly show the maximum LAG capacity in command output, but the platform documentation specifies the limits for each platform type.