The Network Address Trap

Lesson 24 of 35 in Coddy's LAN Labs course.

Every subnet reserves two addresses that no device may use: the network address (all host bits zero, 192.168.1.0 in a /24) and the broadcast address (all host bits one, 192.168.1.255). Assigning either to a machine is a configuration error even when the tool that typed it in did not complain.

netlab check knows the rule and reports it as an ERROR naming the host. Pick any address strictly between the two reserved ones.

Challenge

Easy

Run the check, fix pc2 by giving it 192.168.1.20/24, then ping pc2 from pc1.

Expected output:

ERROR pc2: 192.168.1.0/24 is the network or broadcast address, not a host address
Lab check: 1 problem(s) found
pc2 eth0: 192.168.1.20/24 (mask 255.255.255.0, network 192.168.1.0/24)
pc1 -> pc2: reply from 192.168.1.20 (ttl=64)

Try it yourself

Terminal