Can we run local server over local network without internet access?

Question

Suppose I have a central server and all other local computers are using the server on that machine. Suppose Internet is down, can I access the server through local network? DO we need special settings on router / server level?

Last time I checked, I can't. My laptop runs the server, and I just couldn't use the server on my local desktop.

Thanks.

Answer 1

The (probable) reason you cannot access the server through your laptop is because of DNS not resolving. It is trying to connect to server via an external IP ( the one connected to internet) and of course, that won`t work.

If your server is connected to Internet, it is most probably assigned and accessed via a Domain name, ie: server.mycompany.com.

This server should (usually) be accessible by 3 methods: the DNS name, an external ip, or an internal ip. This last method is what we need to access locally.

If it is a web application you need to access, simply using the internal ip of the server would suffice to access it:

Instead of server.mycompany.com, one would use the ip, ie: http://192.168.0.23

To avoid your laptop being disconnected from the server when internet is down, you could add an entry in your host file that points to the local ip, IE:

server.company.com    182.168.0.23

Of course, this means when outside your local network, you would need to remove this entry to allow the DNS to resolve through the external ip / interface.

Hope this helps, good-luck!

Answer 2

Yes you can if the server is listening on the Local Area Network interface. You can check if the server is listening on the LAN interface by using netstat (on a Windows machine). You could also disable the firewall temporarily to see if this is the cause of your problem.