3Com 3C17205-US Implementation Guide - Page 33

Aggregated Links 33 Aggregated Links and Your Switch s When any port is assigned to an aggregated link (either manually or via LACP) it will adopt the configuration settings of the aggregated link. When a port leaves an aggregated link its original configuration settings are restored. s A maximum of four active aggregations can be created. A maximum of up to four ports may be added manually to any individual aggregation, but any number may join automatically via LACP. There are however a few points to consider: s Switch 4400 Series - The Switch only supports a maximum of four active ports in any individual aggregation. Any extra ports will remain in a standby state and may become active if one of the four active ports fails. s If multiple links are connected between a unit and more than four other devices as shown in Figure 4, only four of the devices will be assigned to aggregated links. The remaining devices will each only have one link made active, that is, passing data. All other links will be made inactive to prevent loops occurring. LACP detects if one of the existing four aggregated links is removed and will then automatically assign one of the remaining devices to the aggregated link that has become free. Figure 4 How LACP works on a Switch with multiple aggregated links