Hello,

I have an OpenWRT router that I configured as WLAN Access Point. DNS, DHCP and everything else are handled by my FritzBox.. It works well from my laptops.

My Android (7) Phones can connect and talk to servers on the internet. Unfortunately, they are not able to talk to the servers in my LAN (which my laptops can !?!?)

If I use IPv4 addresses instead of names on the smartphones, they can contact my servers. Only if I use host names, nothing works.

You surely need more information about my setup. I'm an openwrt rookie and don't know what information you need exactly and how to obtain it, so please tell me what I have to do to give you the information that you need...

Thanks very much for your help!

TheGrue

Sounds like samba or windows IIS is not configured. DNS Is diff than windows or Apple network methods. Android is a basic os and cannot do everything on its own, like network with mixed environments.

There are some windows client apps that allow connections to shared  networkresources.

(Last edited by Notsofast on 1 Jan 2018, 21:21)

Hello Notsofast,

thanks for your input, but that certainly is not the case. I live in a linux-only-household and I'm not talking abou webpages (well, not only). BTW, as I wrote: with the laptops (debian 9) everything is fine.

Examples: (I'm not allowed to post urls so I substituted htper text transport protocol with ht_tp below. That' NOT a typo...

I can access ht_tp://ha/fhem on my raspberry from the laptops, but not from the smartphones. But I /can/ access ht_tp://192.168.178.51/fhem from the phones.

I can ssh to zem from the laptops, but not from the smartphones. I /can/ ssh to 192.168.178.2 from the smartphones

And so on. I suspect some IPv6 dns problem, but that's only a guess.

cu
TheGrue

BTW: WTF? I'm not allowed to post URLs in a forum about a router firmware?!?

Well it sounds like the phone is using its data connex for Internet DNS, which will kill name resolution inside your lan. Plus there are some settings which over ride dns using Google's dns servers. Google has a lot of dung setup to make your phone be connected to Google as primary connex. So you will need to use IP for connecting internal connections through Android devices.

Or setup internal DNS server as a intranet DNS and Internet DNS cache and point your primary DNS on the router to your networks internal DNS server.

This way all internal DNS resolutions will be seen by your android devices and route internally without looping out and back from the Internet.

The Smartphones used a wrong DNS server - no idea why and to whom that IP belongs. Doesn't seem to be one of mine... So I looked in the settings of my Fritzbox, found the DNSv6 server settings, copied that IP and entered it in open wrt unter Network->interfaces->Lan->edit->IPv6 Settings (down in the "DHCP Server" region of the page...) -> Announced DNS servers.

Restarted wifi on the phones and everything is fine

Android smartphones are hard-wired to always use Google's DNSs (8.8.8.8, 8.8.4.4), independently of any local network configuration; if you want them to use your local DNS instead, you must use the firewall to make a redirection.