A Local Area Network (LAN) should work also without Internet, as long as the components you use (PC, gateway, router, server) all have power.
When all is up and running again, disconnect the router from the Internet (just disconnect the Ethernet cable) and see if it works.
Today there is outage in our area, it turns out internal user PC could not visit the file server during outage, I thought it is local, in the same domain network, should it be working even without internet connection? Help me understand this.
This is my network setup, cable into a gateway, gateway connect with a router, router have a server and 5 other PCs connected,
server serve as a file sever, one of the PC also hosts a web application.
How to enable the intranet connection even when the internet (external connection) is down, so that I can still visit files on the map network drive??

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