How to Connect Two Switches to Asus RT-AC88U Router

I ended up resolving this issue by completing the following steps:

  1. Setting the default gateway on the router to the router itself (192.168.0.1)

This partially fixed the issue and allowed the second switch to be connected into the system with only one client without any issues.

However, when the remaining clients were connected into the second switch. None of the clients on the second switch could connect to the network. The clients on the first switch remained unaffected.

  1. Simply the problem by connecting one client at a time into the second switch.

This allowed me to identify that whenever a particular client was connected to the system. It would disconnect all users on the second switch. The client that was causing the issue in this case was a computer connected to the network that was crashed with an error message that was along the lines of ... "Please insert sandisk boot device". When this computer was restarted it no longer caused networking issues when connected to the system.