Adds Part 2 to Investigation 1 to help troubleshoot nested VM issues.

docs/A-Labs/lab2.md

@@ -150,18 +150,35 @@ The _libvirtd_ daemon should be running, and the _id_ command should show that y
 9. Start the graphical `virt-manager` tool by clicking "Activities " and searching for "virt-manager".
 10. Right click on the icon and "Pin to dash" and then run the application or by typing the command `virt-manager` (without sudo!)
 11. Confirm that "debhost" is configured to allow nested virtualisation:
+  * If you have an **Intel** CPU, run the following command. The output of this command should be "Y":
 
-```bash
-# If you have an Intel CPU the following should output "Y"
-sudo cat /sys/module/kvm_intel/parameters/nested
+    ```bash
+    sudo cat /sys/module/kvm_intel/parameters/nested
+    ```
 
-# If you have an AMD CPU the following should output "1"
-sudo cat /sys/module/kvm_amd/parameters/nested
-```
+  * If you have an **AMD** CPU, run the following command. The output of this command should be "1":
+
+    ```bash
+    sudo cat /sys/module/kvm_amd/parameters/nested
+    ```
+
+12. If *neither* of these files outputs the Y or 1, or if you get a "No such file or directory" error, this means nested virtualization **has not been successfully enabled on debhost**.
+
+### Part 2: Troubleshooting Nested Virtualization
+If you confirmed nested virtualization works in debhost in *Part 1, Step 11* above, you can skip Part 2 and move on to Investigation 2.
+
+Let's run through some common reasons why nested virtualization may not be working for your computer, and how to go about fixing them. Keep in mind, this is not an exhaustive list, and *you may have more than one of these issues at the same time*. Just because you fixed one doesn't mean there aren't other problems.
+
+**Important Warning:** Nested virtualization is *REQUIRED* for this course.
 
-You will be learning in the next investigations to perform 3 different types of Debian Linux installs.
+1. Double-check you haven't introduced any typos when running the commands from Part 1, Step 11.
+1. At the VMware Workstation level, open the settings for your debhost VM and check if **Virtualize Intel VT-x/EPT or AMD-V/RDI** is enabled. If not, enable it and try Part 1, Step 11 again. You'll need to fully shut down debhost to change this setting. (Refer to Lab 1, Investigation 1, Part 5, Step 26 for further details.)
+1. **On non-Seneca, personal computers running Windows 11:** If you get an error from VMware that "Virtualization is not supported" (or something similar), you will need to do a bit of online research to fix this issue, as we cannot officially provide tech support for non-Seneca hardware. That said, here are some good places to start:
+   * In Windows' Device Security settings, disable **Memory Integrity** and any other Core Isolation protections. (You are doing so at your own risk.) Restart your computer.
+   * In *Windows Features*, disable all Hyper-V related options. Restart your computer.
+1. **On non-Seneca, personal computers running macOS:** Due to hardware design limitations, nested virtualization is ***not possible*** for M1/M2/M3-based Apple computers at this time. However, nested virtualization will work if you have an older, Intel-based Mac. Check your system's profiler for more details. 
+1. Ask your fellow classmates for help. Many others have run into this issue and they may be able to show you how to fix it!
 
-**Answer INVESTIGATION 1 observations / questions in your lab log book.**
 
 ## Investigation 2: Install Nested Virtual Machines (KVM)