HP 1800 24G Configuration Guide - Page 27

Using the ProCurve Web Browser Interface Using the ProCurve Web Browser Interface Web Configuration Trunk Membership This page allows you to create static trunks. Trunking allows you to assign physical links to one logical link (trunk) that functions as a single, higherspeed link providing dramatically increased bandwidth. This capability applies to connections between backbone devices as well as to connections in other network areas where traffic bottlenecks exist. Port Trunking Support Ports per trunk (maximum) Trunks per switch (maximum) ProCurve 1800-8G 8 4 ProCurve 1800-24G 8 12 The Membership Table has one row for each port and a column for each trunk, plus an additional column for ports that are not members of a trunk. Each row contains radio buttons that are used to indicate which trunk (if any) the port belongs to. Aggregation Mode When incoming data frames are fowarded by the switch over a trunk, the switch must determine which port link in the trunk to use for each outgoing frame. To maintain the frame sequence for traffic flows between devices in the network, the switch also needs to ensure that frames in each "conversation" are mapped to the same trunk link. In order to meet this requirement and to distribute a balanced load across all links in a trunk, the switch uses an algorithm based on the frame source or destination addresses to calculate an output link member in the trunk. However, depending on the device to which a trunk is connected and the traffic flows in the network, this load-balance algorithm may result in traffic being distributed mostly to one port in a trunk. To ensure that the switch traffic load is distributed evenly across all links in a trunk, the source or destination addresses used in the load-balance calculation can be selected to provide the best result for trunk connections. The switch provides six load-balancing modes that apply for both static and dynamic trunks: ■ SMAC: All traffic with the same source MAC address is output on the same link in a trunk. This mode works best for switch-to-switch trunk links where traffic through the switch is received from many different hosts. 2-17