Hi folks, a little troubleshooting help here, please.
I have a Samsung Galaxy S9 with Android 10 rn. I use Firefox as my main browser, but I’ve tried this on others (Internet from Samsung, DuckDuckGo browser) and get the same result.
When I am at home, connected to my personal wifi network I want to connect to my self-hosted server at 192.168.68.137. In all browsers, just starting this week, I get “Can’t connect to the server” or “ERR_ADDRESS_UNREACHABLE”. This just was working fine the other day, but something (???) has changed and it won’t connect. When I am trying this, my phone’s IP is 192.168.68.106 so def on the same lan. And, my phone can connect to 192.168.68.100 without error - it’s just the .137 address it can’t connect to. This isn’t a DNS issue; I am trying to reach it only via the IP address.
The server is definitely up and other PCs can connect to it just fine on the same LAN / 192.168 segment. I’ve tried rebooting the phone, same result. I turned off my pihole ad blocker - same result.
The craziest thing (to me) is that if I disable wifi on my phone, (so now it’s on the cellular network) then connect my Wireguard VPN back into my home network, then I can browse to my home server. That should work, of course, but so should it work for me to connect while on the home wifi network without the VPN.
If anyone has any ideas, I would be very grateful.
EDIT: I rebooted the server and voila! The phone is connecting again. No idea why, but sure, OK. Thanks anyway, folks.
Can you ping the server from your phone successfully? You can use an app like this to check: https://play.google.com/store/apps/details?id=net.he.networktools
Making sure you have layer 3 connectivity first would be a good first step. If you don’t, I would start by troubleshooting at layer 2. Run a packet capture on both your phone and server while trying to connect to determine where the disconnect is. Make sure ARP is resolving properly.
If layer 3 IS working, move up to layer 4 and make sure you are using the correct port, http vs https, etc
I installed the suggested he.net app. Sending its Ping from the phone (.106) returns no responses from the server (.137).
I’ve no idea about the rest of what you wrote, or how to test layer 2 or 3 specifically. I’ve no way to run a packet capture, that I know of. Thanks for trying in any case.