Lesson 23—Troubleshoot Network Issues

Question 1

How can you identify the MAC addresses for all the Mac computer’s network interfaces?

Answer 1

You can identify all the MAC addresses for the Mac computer’s network interfaces from the “ether” line in the output of the ifconfig command in Terminal.

Question 2

What’s the term for the current data rate of a Wi-Fi connection, and where can you access this
information about a specific Wi-Fi connection?

Answer 2

You can view the current data rate, or Tx Rate, of a selected Wi-Fi connection in the Wi-Fi status menu. The Wi-Fi status menu gives you access to important information about your connections and also gives you access to troubleshooting tools like Wireless Diagnostics. You can open the Wi-Fi status menu by pressing and holding the Option key and clicking the Wi-Fi icon in your menu bar.

Question 3

How can you verify basic connectivity to another network host?

Answer 3

You can use the ping command in Terminal to test network connectivity to another network host by sending a ping packet and waiting for its return.

Question 4

How can you verify that DNS host name resolution is working?

Answer 4

You can use the commands nslookup, dig, host, or dscacheutil in Terminal to test name
resolution against the currently configured DNS server.

Question 5

How can you verify that the system can establish a connection to a remote network host?

Answer 5

You can use the traceroute command in Terminal to verify the connection hops between your Mac
and a remote host.