It seems that my Raspberry PI 3B is very picky about which switches it works with when booting using PXE.
When I connect the PI to my regular non-POE switch, PXE boot works fine. When I connect it to my first POE switch, PXE does not work. At first, I thought my POE switch is damaged, so I bought a second one (completely different model and maufacturer) and tried it with that. But still the same problem. Most of the times, dnsmasq does not even log a DHCP request through these switches, and in rare cases it gets the request and sends 2 files through tftp and then no more files get requested.
But I know the POE switches are working quite well for everything else. If I connect my computer to it, i get internet connectivity and all this, if I connect a raspberry pi that boots from SD-card, it boots fine and gets internet connectivity as well.
So the issues are only related to PXE.
The funny part is, that when I do something like this:
Router -> POE-switch -> regular switch -> PI
PXE boot works again. It only does not work when the PI is connected directly to the POE switch.
I think the problem is not really that it's a POE-switch, I believe that the PI is just very picky with the switch. I bet there are regular switches out there that would not work as well, just because they do a tiny little thing different than the others.
But if that's true, I don't want to buy another switch, and then another switch until one works. Does anybody use PoE and PXE at the same time? If yes, what switch do you use?
I can tell you, these 2 don't:
- edimax ES-5104PH
- Autoeye 4-Port PoE switch
Notes I know that the PI does not support PoE without a splitter. I have a splitter and also tried it, but it does not make a difference. If i connect the PI with the splitter to a regular switch, PXE works. If i connect the PI with the splitter to a PoE switch, it doesn't. Sad story :(