User David shows us how to configure ALTQ, a network interface manager framework. If you ran into the issue, follow the link below for the full instructions.

Screen-Shot-2016-03-22-at-2.06.17-AMALTQ also known as alternative queuing, its a framework to manage queue on network interfaces. My FreeBSD box requires this function to enable and do QoS things such as limiting network bandwidth per customers based on their IP address or limiting the network bandwidth based on protocols.

I used HP DL 160 with intel I350 dual port network adapter (igb0 & igb1), running on FreeBSD 10.2-RELEASE-p14 amd64.  After configuring and enabling ALTQ on that interfaces, I try to load pf.conf and get the following error:

pfctl: igb0: driver does not support altq

Full tutorial: