Connect to a device having Static IP of 10.0.0.x on a 192.168.1.x Network

Question

I do see that there are many answers to this question however my question I believe is slightly different as it is directed more at potential change to my router. I'm seeking to know if the below is possible.

Question

Do routers have the ability to connect devices having IP Addresses of both the typical 192.168.1.x and 10.0.0.x. Do routers support this capability or do they ONLY have the ability to connect to a single subnet?

My story which is similar to almost everybody else in that I installed a new router and wish to update my server IP with minimal effort. My server room is currently inaccessible. I wish for my existing devices to remain connected to my router and not lose their connection to the Internet while also being able to remote into my server (Putty as an example) having the old IP Address of 10.0.0.x. My laptop of course has the new IP Address of 192.168.1.x.

How can I connect to my server from my laptop via my new router? Again, can a change be made to my router to allow for this temporary connection without affecting my currently connected devices?

• Laptop (192.168.1.x)
• Router (192.168.1.x)
• Server (10.0.0.x)

Laptop ---> Server

I made and Attempt to set a Static route to my server however this did not work as static routes still need to 'Route' the devices that connect to that route. My connection is a straight shot from my router to my server.

So again, I could not find a solution that would allow me to update my router in order to get this to work. Had to utilize another solution which is below:

Answer and Implemented Solution Provided by LPChip

Answer 1

As long as a wire is attached to the machine, the ip address will not be something that stops you from connecting.

That said, the subnetmask does specify what devices your network can see.

So if you have 2 devices on the same network (they are connected physically to the same router) but one device has a range of 192.168.1.x with a subnetmask of 255.255.255.0, and another device with a static ip of 10.0.0.x with a subnetmask of 255.255.255.0, the devices will not be able to see eachother.

However, given that one device has a static ip address, if you were to set that to DHCP, it would get a proper ip address from the router and it would work again.

But that is not the only way to connect to this machine. From any other device in the network, if you change its ipaddress to static (it can be the same ip address it had before, but it has to be static), you can then add a 2nd ip address. If you add a second static ip address in the 10.0.0.x range with a subnetmask of 255.255.255.0 your device will be able to communicate with the other device just fine. You could of course also just set it to the static ip address without adding a 2nd, but then you would lose the ability to communicate with the router or any of the other devices in your network.

It is strongly adviced that once you established a connection to the 10.0.0.x device, to change its ip address so it is in the range of your 192.168.1.x network.

So TL;DR: On your laptop, set its ip to static, can be the same ip address. Then head over to advanced, ip addresses tab, add another ip address, this time in the range of 10.0.0.x, and now you can ping the server and if RDP was enabled previously, RDP into the server normally. Once there, change the server's ip address to an 192.168.1.x address so the rest of the network can also access the server.