Load Sharing On The Switch; Configuring Switch Load Sharing - Extreme Networks ExtremeWare XOS Guide Manual

Configuring Slots and Ports on a Switch

Load Sharing on the Switch

Load sharing allows you to increase bandwidth and availability by using a group of ports to carry
traffic in parallel between switches. Load sharing allows the switch to use multiple ports as a single
logical port. For example, VLANs see the load-sharing group as a single logical port. Most load-sharing
algorithms guarantee packet sequencing between clients.
If a port in a load-sharing group fails, traffic is redistributed to the remaining ports in the load-sharing
group. If the failed port becomes active again, traffic is redistributed to include that port.
NOTE
Load sharing must be enabled on both ends of the link or a network loop may result. The load-sharing
types (dynamic, static) must match, but the load-sharing algorithms do not need to be the same on both
ends.

Configuring Switch Load Sharing

To set up a switch to load share among ports, you must create a load-sharing group of ports. The first
port in the load-sharing group is configured to be the "master" logical port. This is the reference port
used in configuration commands. It can be thought of as the logical port representing the entire port
group.
All the ports in a load-sharing group must have the same exact configuration, including auto
negotiation, duplex setting, and so on. All the ports in a load-sharing group must also be of the same
bandwidth class.
The following rules apply:
• One group can contain up to 16 ports.
• The ports in the group do not need to be contiguous.
• A load share group that spans multiple modules must use ports that are all of the same maximum
bandwidth capability.
To define a load-sharing group, you assign a group of ports to a single, logical port number. To enable
or disable a load-sharing group, use the following commands:
enable sharing <master_port> grouping <port_list> {algorithm port-based}
disable sharing <master_port>
NOTE
Do not disable a port that is part of a load-sharing group. Disabling the port prevents it from forwarding
traffic, but still allows the link to initialize. As a result, a partner switch does not receive a valid indication
that the port is not in a forwarding state, and the partner switch will continue to forward packets.
Adding and Deleting Ports in a Load-Sharing Group
Ports can be added or deleted dynamically in a load-sharing group. To add or delete ports from a
load-sharing group, use the following commands:
configure sharing <master_port> add ports <port_list>
58 ExtremeWare XOS 10.1 Concepts Guide