Network, broadcast and usable host addresses

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Identify /24 boundaries and correct the PC addresses.

Sign in and launch

First: Static IP Addressing in a Single Subnet

Network

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SW1 connects PC1 at 192.168.1.0/24, PC2 at .50/24 and PC3 at .255/24.
Initial addresses: .0, .50, and .255. No gateway is needed.
Open a console

1. Inspect broadcast

In a /24, .0 is the network address, .255 is broadcast, and host addresses are .1–.254.

PC1

timeout 120 tcpdump -U --immediate-mode -i eth0 -w /tmp/lab-subnet.pcap "arp or icmp" &
capture_pid=$!
sleep 1

PC1

ping -n -c 1 -W 1 -b 192.168.1.255
ping -n -c 3 -W 1 192.168.1.50

PC1

sleep 2
kill -INT "$capture_pid"
wait "$capture_pid" || true
tcpdump -nn -e -r /tmp/lab-subnet.pcap

Compare the broadcast frame to ff:ff:ff:ff:ff:ff with unicast traffic to .50.

2. Correct the addresses

PC1

ip address del 192.168.1.0/24 dev eth0
ip address add 192.168.1.1/24 dev eth0

PC3

ip address del 192.168.1.255/24 dev eth0
ip address add 192.168.1.254/24 dev eth0

3. Test connectivity

PC1

ping -n -c 3 -W 1 192.168.1.50
ping -n -c 3 -W 1 192.168.1.254

PC3

ping -n -c 3 -W 1 192.168.1.1

All three pings should succeed.

Validation

Click "Check". Once all steps pass, click "End".