There are many different options for access points that you might be using as well as a wide range of switches too. I recently moved from my 4506 chassis at home to a 3560G (to cut my electric bill!). I recently received a new Cisco Catalyst 9117AX access point and tried to use it on my network. As soon as I powered it on, I saw that it connected to my WLC just fine, but that there was an issue:
Power over Ethernet Modes
There are multiple types of PoE power that you might be utilizing. These different standards vary in the output wattage that they provide. These standards include:
- 802.3af – 15.4 Watts Max
- 802.3at – 30 Watts Max
- 4-Pair PoE (PoE++) – 60 Watts Max
- 802.3bt – 100 Watts Max
Depending on which type your switch can provide might determine which devices you will be able to power. Some devices, when not provided enough power, will cease to function completely. Others may operate in a degraded state.
Access Point – Low Power Mode
A lot of Cisco access points have the ability to operate in low power mode. This involves the access point reducing performance capabilities to reduce power. For example, I recently connected my 9117AX as I mentioned and ever after associating, the LED’s were doing this:
Upon checking the documentation, this was signaling low power being provided to the access point (which I already knew). In my case, as with other access points, this means that my AP was operating with certain radios disabled. The access point works just fine and serves clients, just not at peak performance.
How to fix
In my case, I do not want to shell out the cash for a PoE+ or better switch at the moment. My 3560G is doing just fine for what I need. I do want my access point to operate at full power though. My best recommendation if you do not want to upgrade your switch is to go the power injector route. The documentation stated my AP would work at full feature set with 802.3at power. I grabbed a Meraki PoE injector last night on eBay for $5.00 so in a week or so, I’ll be running at full power!