Masks and Gateways

Lesson 34 of 35 in Coddy's LAN Labs course.

Now the warnings. h2 has the wrong mask (/25 in a /24 floor), which the check reported as a mask mismatch with its neighbors. h4 has no gateway at all.

And one fault the check cannot see: h3's gateway is 192.168.20.9, an address inside the right subnet that no device owns. The lint only knows the subnet rule; a ping would show no device answers at gateway. Point both second-floor hosts at the router's real address, 192.168.20.1, and the check should come back clean.

Challenge

Medium

Fix h2's mask (keep 192.168.10.12, use /24), set the gateways of h3 and h4 to 192.168.20.1, then run the check.

Expected output:

h2 eth0: 192.168.10.12/24 (mask 255.255.255.0, network 192.168.10.0/24)
h3: gateway 192.168.20.1
h4: gateway 192.168.20.1
Lab check: no problems found

Try it yourself

Terminal