Link aggregation, which is also known as "port trunking" or "NIC bonding", allows you to aggregate multiple Ethernet network ports into one virtual interface. The aggregated ports appear as a single IP address to your system. Link aggregation is useful to increase the link speed beyond the speed of any one single NIC or to provide basic failover and fault tolerance by redundancy in the event any port or switch fails. All traffic that was being routed over the failed port or switch is automatically re-routed to use one of the remaining ports or switches. This failover is completely transparent to the system using the connection.
To create a link aggregation group (LAG), proceed as follows:
For each LAG, select the interfaces you want to add.
A group can consist of a configured interface and/or one or more unconfigured interfaces.
To use a configured interface, select it from the Convert Interface drop-down list. To use unconfigured interfaces, select the respective checkbox(es).
Enable the LAG.
Activate a group by clicking the button Enable this group.
Once the link aggregation group has been configured, a new LAG interface (e.g., lag0) becomes available for selection if you are going to create an interface definition on the Interfaces tab. On top of the bonding interface you can create one of the following:
To disable a LAG, clear the checkboxes of the interfaces that make up the LAG, click Update this Group, and confirm the warning message. The status of the LAG interface is shown on the Support > Advanced > Interfaces Table tab.