Help with bizarre Pi WiFi issue
I'm building my first Signal k box based on a Pi-5 with a SH-RPi. I'm having wifi issues when android devices connect to the Pi when the Pi is the AP.
If I make my phone (pixel 7 android 15) the AP, then the Pi can connect to it fine and I get no network issues. But my phone can't be part of the system.
If I make my Yacht Devices YDNR-2 router the AP, again no problems. However the YDNR does not support allocating fixed IP addresses, so I can't run in this as my signal k server address would be subject to the vagueness of DHCP and connection order etc.
So I made the pi the AP. The YDNR connects to it and there is absolutely no problem there. 0% packet loss.
But when either (or both) my phone or the android 13 tablet that will be the on deck display connect, I get sporadic connection with 80% packet loss when the Pi pings either device.
I've tried fully dynamic IPs and fixed IPs configured in the Network Manager.
The only other thing I can think of is that the be YDNR is 2GHz only, whilst both android devices can be 5G. So i tried turning 5G of with
Followed by an down/up, but that made no difference?
Anybody have any idea what this could be?
9 Replies
Hmmm there is still something a bit funny when I use the YDNR 2 as the AP. If I ping from the Pi to the YDNR, I get 0% loss with a 3.6ms return time on every ping.
But if I ping the tablet from the Pi, whilst I also get 0% packet loss, the return time varies from 2ms to at least 500m, average 115ms.
I know that is probably going via the YDNR, but 500ms is a long time on a local network?
Here is a video showing the problem (sorry for the shaky hand cam)..https://youtu.be/k-c4fRE75GQ
@Gregw I'm having similar problems. It's the inconsistency that's so frustrating! We can sail all day with our Android tablet connected to the Pi as an AP no problem and the suddenly it's dropping connections every few seconds, our even failing to connect to the AP. I also see similar failures from my Linux laptop connected to the Pi AP, but if I connect the Pi to the internet, e.g. through wlan0 to a phone hotspot, then the laptop behaves fine, but the tablet still has problems. All this seems to point to the NetworkManager and the magic it's doing to make the hotspot. I have tried removing the nftables rulesets the nm creates, but that doesn't help.
Hmmm maybe we should try installing Ubuntu instead?
Unfortunately I'm not in a position at the moment to start from scratch. Using an old phone as an AP, which doesn't have a valid SIM in it, and connecting the Pi and all the clients to it works fine. I'll keep looking at this and let you know if I find a fix.
I'll give the Ubuntu approach a go and tell you if it is worth the effort
Unfortunately I've fried my pi's SD port.. It literally melts any card or in it. So I can boot another os unless I remove the SSD!
Have you tried with the tablet right next to the Pi? In your video there's a board in the way. I've had very poor WiFi/BT connectivity until I connected an external WiFi/BT antenna to my pi.
I've had to tablet and phone right next to it. Also when the android device is the AP there is no packet loss. Even stranger, when the Pi is the AP, there is 80% packet loss when it pings the android, but only 5% packet loss when the android pings the Pi!
Did you check the logs (journalctl) of the Pi?
maybe you are not alone: https://forums.raspberrypi.com/viewtopic.php?p=2269002&hilit=pi5+wifi+ap+packet+loss#p2269002
Latest firmware installed? Maybe a bug in the Wifi-firmware that got fixed.
I think my firmware is the latest? But I will check when I can (it was so much easier to play with when it was installed in garage rather than on the boat)! Good to know I'm not alone and not going crazy