Not working with PoE switch

So right now I’m just running a plain raspberry pi 4b with the basic home assistant os.
If I plug the eternal port into a normal Ethernet router it works perfectly. If I plug it into a PoE netgear router it doesn’t connect.
Now: I already have a home assistant yellow (PoE version) plugged into the same PoE router and it works perfectly.
Also: I tried plugging my raspberry pi 4b into a normal router but used a PoE plug in adapter that came with one of my cameras. Again it doesn’t work.
It seems like raspberry pi 4b just isn’t PoE compatible. But that doesn’t seem right at all because other people say they do it. Is there something I need to configure specifically to support PoE vs a normal network connection?
FYI: I’ve been an engineer for 25 years working on Linux based systems. I’m just new to raspberry pi hardware and new to home assistant os.

What do you mean by “doesn’t work”?

Do you mean it doesn’t appear on the network or do you mean it won’t power.

The Pi4 doesn’t have POE unless you fit a POE hat.

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I mean it doesn’t connect to the network.
I’m using the same external power supply in every one of my tests.

This all started with a PoE hat on. That wasn’t connecting. So I took the hat off and started using a regular power supply to narrow down the problem.
So right now if I plug the network cable into a non-PoE router it works. If I plug into a PoE router it doesn’t connect. The only variable is the type of router.

which Netgear ? , how is the ports configured ? passive PoE option, or not ?
And which PoE - Type?

And what kind of “Adapter” ?

there are 2 kinds, 1 which provides power, and 1 which splits-out the power provided

PS: And when you keep saying “Router” i still assume you mean as Topic header ( A switch )

How to help us help you - or How to ask a good question.

I actually have three switches:
Netgear GS724TP that is only used for PoE devices. Right now it only powers five Ring Cameras and the Home Assistant Yellow. There is also a Ring Alarm base unit on it.
Netgear GS716T that is only used for the hardwired televisions I have in every room.
Netgear GS724T that connects to normal cat6 outlets in every room. But only my work laptop and a Netgear NightHawk are plugged into that. The nighthawk is only used for cells/tablets/laptops.
All three switches were set back to factory defaults. I only need basic switching capabilities.
The three switches go into a Cisco 1921 router with the 8 port switch module. Then that goes to a fiber modem.
That’s my entire network setup. I set that up during Covid because I was working remotely with two kids doing remote school. I don’t even get close to the bandwidth capacity of this network.

I only started using PoE about a year ago. I will look up what you said. It powered the cameras and the HA Yellow so I didn’t look into the settings further.

I have two 4B modules and two cards with the HA installed. I randomly use one or the other to test so I know it’s not simply a manufacturing defect in a single card.

If I plug either of them into the GS724TP I don’t get network connectivity. I am still using a standard power supply to power the 4B directly. So it boots but doesn’t get a good connection (and the HA OS doesn’t seem to accept the ifconfig command so that’s useless).

If I plug either of them into the GS716T or the GS724T I do get network connectivity. Again using the same 4B power supply for power.

As a side test out of curiosity I plugged the GS724T into a Ring POE15M-1AFE single port PoE adapter and then into the 4B. I still used the same power supply for the 4B. I don’t get network connectivity that way either.

Tomorrow I am going to borrow my daughter’s 4B running PI OS. I will try connecting that to the GS724TP. Hopefully that will tell me if I should focus on hardware or os since the only difference between hers and my two is the os flashed into the SIM card.

And thank you for the help. We don’t use PoE in my line of work. So I am pretty new at that too. I only added it about a year ago when I started installing cameras and the HA Yellow.

PI 4b should support POE, but i have no idea of which type/how much it requires, the GS724TP should be able to deliver enough wattage , so that doesn’t seems to be the issue ( it does have a total limit (192W and a port-limit(30 wat) for what i can see, but that should be enough
You could first try to disable POE on that particular port, to see if PI4 likes that better … that would be my first attempt , before diggin deeper into the settings

O M G !! You do know that PoE stands for “Power over Ethernet” ?

Oversimplified explanation: PoE is a specific variation of the Ethernet standard, to “inject” low-voltage power to some of the wires in the Ethernet cable at the router/switch end; and at the device end a PoE Splitter extracts the power to a separate power connector, so the device sees only data on its Ethernet connector. Both the Injector and/or Splitter can be built-in, or external devices. See a more detailed explanation.

PoE is particularly useful for cameras, because cameras are often located where there is no power wall socket handy; and PoE allows both data and power to be supplied over one wire (which doesn’t require a licensed electrician to install). For most other devices the extra cost of building in the PoE splitter hardware isn’t justified, but adding a PoE splitter adaptor can do the same job.

Power where it was not expected is a great way to “let the smoke out” ! You need PoE at both ends, or not at all.

Your first post correctly identified the situation

  • connecting a regular Ethernet port to a regular Ethernet switch works perfectly
  • connecting a PoE Ethernet port to a PoE Ethernet switch works perfectly
  • PoE and non-PoE do not mix, any more than diesel in a petrol car, or a square peg in a round hole.

Maybe you are assuming that because your Home Assistant Yellow is the “PoE version” (mentioned in your original post), that all the regular Raspberry Pis are as well. Or maybe that because “other people” say that RasPi can do PoE, that it works out-of-the-box.

According to Raspberry Pi 4 Tech Specs, “Power over Ethernet (PoE) enabled (requires separate PoE HAT)”.

Fortunately your 4Bs recognised the PoE coming down the wire, but without a PoE HAT to split the power out they turned off the ethernet port temporarily, resulting in no permanent damage.

As expected. The switch does not provide PoE, yet you added a PoE adaptor to split the power out, and used an external power plug. Not only was the PoE adaptor serving no useful purpose - it was actually interfering with the signals in the wires in the ethernet cable, by trying to split out power which wasn’t there.

And hiding in the 4th post is I suspect the major clue …

Surely having the PoE HAT on or off is actually a significant variable ?

With PoE HAT off, it should connect to a non-PoE Ethernet switch.

With PoE HAT on, it should connect to your PoE switch. If it doesn’t work in this case you should look at what is needed to configure your PoE HAT, or whether the PoE HAT is faulty.

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Im sure he ( and i understand ) what POE stands for, However he apparently didn’t disabled this feature in his advanced managed switch , it seems that the PI didn’t got toasted , whether that’s doe to PI shutting of , or Actually the PSE did the job, i would leave unspoken. ( i fact, it was most likely the PSE, as it wont provide any power if the Device is not a POE )
But it appear that OP wasn’t aware that PI4b needs the HAT, regardless of his PSE can provide POE+ ( Yes, Could be that the HAT he used was faulty, and/or didn’t support POE+)
Yes he should have “consulted” the GUI for the PSE , to check the port settings before plugging anything in, but seems like he “tested” the PI after in a non-poe, and it was still working, so simple method would be to turn-of POE on the port, if possible.
Just resetting the PSE, without know what default settings is, is not a good idea.

Anyway, if it’s not a POE device, the switch will not provide power, if the device is not a POE+, the switch will only provide POE ( Not + ) , but should still be enough to power the PI, if he doesn’t have tons on equipment attached to the usb-ports ( which he also seems to state, that he doesn’t have ( as it works with the standard PS, for the PI )

Either their is a mis-match with his port-settings( in PSE) and the HAT config, or the HAT is faulty

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