PROBLEM: When I lose internet connectivity my internal network loses connectivity, meaning, I am unable to connect to any other device on my network while the internet connection is down.
I have an internal wired network in my home that consist of the following:
- 12 Foscam IP cameras (wired)
- Windows 2012 R2 Server (IIS FTP Server and IIS Web Server)
- Windows 10 Professional (8 machines in total)
- Ubuntu 20.04.1 (A minecraft server for my kids)
- Two five port unmanaged switch
- One five port managed switch
- One 16 port unmanaged switch
- Linksys Mesh Wifi Router
- Netgear Cable Modem
Every device on this network has a statically assigned IP number in the 192.168.0.0/16 subnet. The only device directly connected to the Netgear Cable Modem is the Linksys Mesh Wifi Router.
When internet connectivity is down I open a command prompt on any computer and attempt to ping any other computer or any of the ip cameras and the ping times out. Each camera connects via FTP to my FTP server and uploads a continuous stream to the FTP server and connects via IP number only. When the internet connection is down, the cameras cannot reach the FTP server. (DNS is not involved). The kids (who am I kidding, I play too) cannot connect to the Minecraft server even though they attempt to connect using IP number only. In short, there is NO intranet connectivity at all if the internet connectivity goes down.
What I have tried: I have ensured that the only thing connected to the Linksys Mesh Wifi Router is the 16 port hub in an attempt to isolate the network from the hub if the router goes down or loses connectivity to the internet. If I disconnect the ethernet cable between the router and cable modem I am able to ping any device on my network. If I disconnect the ethernet cable between the 16 port hub and the router I am able to ping any device on my network (I have tested this while the router has connection to the internet and while it is unable to connect to the internet). This issue only occurs if the connection within the router goes down while it is still physically connected via ethernet cable to the rest of the network. When the connection is restored AND I reboot the router connectivity is reestablished within the internal network.
If anyone can shed light on this phenomenon, I would certain appreciate it.