How to get the type of PoE power supplied

I understand that there are several devices that support OpenWRT and PoE.
If so, is there a way to know if the device is powered by 802.11af or 802.11at?

it's in the specs ?

That's actually not very important, 802.3af and 802.3at are not different standards, 802.3at is a superset of 802.3at that (amongst other details) provides more of a power budget. By providing 802.3at, 802.3af devices will also work.

The relevant question is rather: Is the device 802.3af/at/bt "active PoE" at all? There is also a nonstandardized "passive PoE", and for that basically every manufacturer makes up their own standard. Some devices (Ubiquity access points for example) use a 24 volt "passive PoE" that is not compatible with the 48 volt 802.3-whatever "active PoE."

As for what standard or variant of PoE individual devices provide or use, you would have to consult datasheets and manuals, sometimes it's also noted in our OpenWrt wiki or on wikidevi.

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If you want to check this on the powered device: No. Or at least. Not in general.

A device could implement some way to signal its power source and capabilities, whether or not PoE is a part of it. But my experience is that the actual power source often is hidden by the power supply. For example: You can tell that there is a PoE hat on an RPi4, but you can't tell if the supplied power comes from it or the USB-C alternative input. The same goes for a Netgear GS108Tv3. It can run on PoE or an external power brick, but the SoC and OS has no clue which is used. In fact, it won't see much difference at all between the GS108Tv3 and the GS308T (which can't be powered by PoE).

For 802.3at (not 11 - I often do that too, and get the wireless power jokes in return :slight_smile: then LLDP could be part of the equation, and you could in theory see the negotiated values. This is all theoretical. I don't know of any real examples.

Power sourcing devices usually provide much more information, allowing you to see configured and negotiated values as well as measured consumption.

I understand that I don't know if the power is supplied by poe.
If so, is there any way to get the power supply figures? (in a similar way to the ubus)

Look at the specs on the manufacturer’s website. It will have the poe type (passive, 802.3af/at/bt) and the maximum power consumption of the device.

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