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; for example: ifconfig | grep ether

(The Network Utility has been depreciated with macOS Big Sur.)

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 on the Wi-Fi status menu.

The Wi-Fi status menu gives you access to important information about your connections and also allows you to access troubleshooting tools like Wireless Diagnostics.

You can open the Wi-Fi status menu by pressing and holding the <kbd>Option</kbd> 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.

(The Network Utility has been depreciated with macOS Big Sur.)

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.

(The Network Utility has been depreciated with macOS Big Sur.)

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.

(The Network Utility has been depreciated with macOS Big Sur.)

Question 6

What are three common issues that can interrupt network services on a Mac?

Answer 6

These three common issues can interrupt network services on a Mac:

1. Local issues: Usually related to either improperly configured network settings or disconnected network connections
2. Network issues: Use the output of network-related Terminal commands to help investigate possible causes
3. Service issues: Related to the network device or service you are trying to access.