I have a computer and two notebooks and would like to make a small private test network (192.168.178.0). Can the computer in the case with the IP 192.168.178.10 at the same time be the gateway and the DNS for the two notebooks? So that the computer gets registered in the Ipv4 setting practically the 178.10 and as standard GW and DNS as well as the 178.10. The notebooks then the 178.20 and .21 for my sake and as their default gateway / DNS then again the 178.10. Should work like that, right?
Naturally. For this purpose, a DNS server must be running on the PC. Best also a DHCP server, so that clients automatically get the correct GW / DNS address.
No, that would not work. A gateway you need if two or more networks want to connect via a router in two (or more) networks. If the notebooks, the computer and the FritzBox are in the same network you do not need a gateway, even if running on the computer, a DNS and DHCP server. If you enter your own IP address as gateway with the computer, it simply does not work.
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