Another option we should consider addressing is link aggregation, which can be configured by clicking on the LAGGs tab on the (assign) page. Link aggregation (usually abbreviated as LAG) allows us to combine multiple ports in parallel, which accomplishes two goals. It increases the amount of throughput (for example, if you have two trunk ports per switch, you will have more throughput than you would with a single port), and it also provides some redundancy in case one or more ports go down. The LAGGs option does not refer to an interface; rather, it refers to LAGG, the FreeBSD link aggregation and link failover driver. Typically, trunk ports involve some form of link aggregation; with some switches, trunks have to be configured as pairs of ports.

To add a new LAGG interface, click on the Add button on the LAGGs tab. This will take you to the LAGG Configuration page. In the Parent Interfaces listbox, you can choose the interfaces that will be used for this link aggregation. In the LAGG Protocol drop-down box, you can select which protocol to use on the interface. The choices are as follows:

When you are done making changes to the new LAGG interface, click on the Save button. The new interface should now be listed in the table on the main LAGGs page.