Asus router problem with a.applovin.com

[mikeh2]

Asus RT-AC1900P using latest firmware from May 2021 -- 3.0.0.4.386_43129-g60defb2
It is not directly online, its WAN port is connected to a LAN port on my main router. Lots of problems, it is pretty much non-functional. It thinks its off-line and connected devices can not access Internet. But, pings from the router work (Network tools -> Network analysis). So, too nslookup from the router works. Big clue was running Netstat in the router. It showed many connections to a.applovin.com. My main router blocks this domain.

Anyone have any idea why Asus needs to communicate with applovin.com?

screen shot of netstat here

https://twitter.com/x/status/1409974316343738371

 

[dave14305]

If the main router is blocking a.applovin.com with 0.0.0.0, then it's just a cosmetic problem with reverse lookup of the 0.0.0.0 address from the ASUS to the main router. netstat -na on the ASUS probably shows all those LISTENing connections on 0.0.0.0.

 

[mikeh2]

You were correct. Thanks.
The domain was indeed blocked using DNS that returned 0.0.0.0. Seems like a bug that netstat tries to resolve this IP address to a name, but it does. Of all the domains blocked with an IP address of zero, a.applovin.com was the first one alphabetically.