Problems

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8 of 277 problems

Title	Topic	Acceptance	Difficulty	XP
How Big Is a /24?How many IPv4 addresses does the block 10.0.1.0/24 contain?easyNetworking3 XP	Networking	New	easy	3
Overlapping NetworksWhich pair of networks overlaps?mediumNetworking5 XP	Networking	New	medium	5
DNS Record TypesWhich DNS record makes www.example.com an alias for another hostname (for example a load balancer's DNS name)?easyNetworking3 XP	Networking	New	easy	3
TCP vs UDPWhy does DNS traditionally use UDP for normal queries?easyNetworking3 XP	Networking	New	easy	3
HTTP Status CodesA load balancer returns 502 Bad Gateway. What does that usually indicate?easyNetworking3 XP	Networking	New	easy	3
What TLS Certificates ProveWhen your browser validates a server's TLS certificate, what is it mainly verifying?mediumNetworking5 XP	Networking	New	medium	5
Well-known PortsWhich mapping of service to default TCP port is correct?easyNetworking3 XP	Networking	New	easy	3
127.0.0.1 vs 0.0.0.0An app inside a container listens on 127.0.0.1:8080. The container is started with -p 8080:8080, but requests from the host fail. Why?mediumNetworking5 XP	Networking	New	medium	5