I have a FritzBox 7270 v3 as a WLAN access point for my mobile devices. This box is attached via LAN to my cable router (Hitron CVE-30360) as well as my NAS (QNAP TS-421).
My NAS and my cable router are configured to be accessible via internet and I can access them without issues.
What I can't do is accessing my NAS via mobile device when connected via my WLAN. I can't use the QNAP apps, I can't access the web frontend but I can access the front end from my cable router and my fritzbox.
So I can access everything from my WLAN except the devices attached via LAN to the cable router.
I am lost. How can I configure my FritzBox to work as a simple switch? It should just pass every request without checking ports.
Any ideas? Does my FritzBox even support what I am looking for?