The sub-interafaces are assigned to unique IP addresses as well. On an Aerohive BR-200 or BR-100 router, the sub interface IP address is default-gateway address of the Network mapped to the VLAN which are created in the Network Policy. On an Aerohive AP, the sub interface IP address might be the gateway address for a network if the access point is functioning as a DHCP server.
When you configure a new DHCP server you assign the MGT sub-interface using the "Interface" drop down menu.
To assign the newly created DHCP server settings to an access point go Monitor -> Place a tick in the checkbox to the left of the access point you want to act as the DHCP server -> Modify (button) -> Service Settings -> DHCP Server and Relay. In the "Available Servers" area you should see the DHCP Server settings you created. Click on it followed by the ">" button to move the DHCP server settings to the "Selected Servers" area. Finally click on the "Save" button at the top of the screen.
If you had another access point that was going to act as a DHCP relay you would need to create a DHCP relay configuration and assign it to that access point in the same area.
I always use the sub-interfaces so that if I ever need to add a second DHCP service I can just add it using interface mgt0.2.
Some Aerohive access points have limited routing capabilities. This functionality can be enabled in the "Device Function" drop down menu you have shown above. If the access point does not have this functionality then it will not be available in the "Device Function" drop down menu. It is worth noting that no Aerohive access points are fully featured routers.
I run an AP370 at home and I have it connected to my router. The router's function is to be a router while the AP370:
- Is the access point (I have disabled the SOHO wireless functionality in my router). Wireless without airtime fairness is just rubbish.
- Is my layer seven firewall
- Gives me Private PSK functionality (so I can see who is accessing what)
- Has a mesh connection to another Aerohive access point on the other side of the house - full wireless coverage across the house :-) This is important as we have a number of smartphones and tablets that can't transmit across the entire house. With the second access point the smartphones and tablets on the far side of the house only have to transmit to the access point on that side of the house.
- Is my reporting engine (well the HMOL is actually :-))