Lack of arp/layer 2 isp, routing. There is also a mistake inside the DNS part. DNS queries are done from the client - and this is actually true for a majority

Lack of arp/layer 2 isp, routing. There is also a mistake inside the DNS part. DNS queries are done from the client - and this is actually true for a majority of client/server requests - by opening a dynamic random port above 49152.