I just moved to a new place and internet is not setup yet so I'm using my phone's hotspot to get online. While developing a Python client-server program I found out that devices connected to Android hotspot cannot communicate with each other. When I ping one computer from another I get a "Destination host unreachable" message. This must be some sort of client isolation. Does anybody know how to turn it off? Using latest crDroid on Android 9.

[UPDATE] I run a few more ping tests and they seem pretty inconclusive. I got some hits but the results vary between 'Host unreachable', 'Request timed out' and various TTL times (6ms to 4000ms).

  • Android uses hostapd as its AP daemon. hostapd.conf file which AOSP creates doesn't contain ap_isolate=1. But may be your OEM has added that to configuration file. You can check that with root: cat /data/vendor/wifi/hostapd/hostapd_*.conf. Do you ping the hosts by IP or hostname? – Irfan Latif Sep 1 '19 at 7:51
  • @IrfanLatif I pinged the hosts by IP that I found from executing ipconfig on cmd. I found the hostpad_wlan1.conf file using a root browser and I can confirm that there is no ap_isolate=1 line in there. Maybe it's 1 by default and I should write ap_isolate=0? As I said I'm using a custom ROM so not sure what you mean by my OEM (wouldn't that be Xiaomi for example?). – Frank F. Sep 1 '19 at 12:39
  • Sorry I missed the custom ROM point. ap_isolate is not set by default. There must be some issues with your networking. Use tcpdump or iptables -j LOG for troubleshooting. – Irfan Latif Sep 1 '19 at 12:43
  • Updated the post with new data. – Frank F. Sep 1 '19 at 14:03
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    I have tried with Android 9 by HTC and the connection between clients works. Although I had to wait for it for about 2 minutes (been waiting on a ping loop). – Ondra Žižka Mar 30 at 0:31

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