One computer - different subnet

[dcol]

I have one computer that has an address of 192.168.100.105 that I want to access from the 192.168.1.x subnet as 192.168.1.105. I cannot change any computer IP because of licensing issues. So I am forced to try and access this one computer as 192.168.1.105 while leaving its IP @ 192.168.100.105. Any changes to the network on this computer will kill the license, which cost thousands of dollars. I also need to use this computer as a file server to the 192.168.1.x subnet.

I do have an unused interface on the OPNsense box that I can set to 192.168.100.x. I can bridge them but the issue is I need to use 192.168.1.105 on the existing subnet to get to the 192.168.100.105 computer. Maybe NAT them?

What is the best way to do this? If even possible.

[hbc]

What about a second NIC for this host in your 192.168.1.0/24 network? Then you access your files via this interface and the old up is still valid

[fabian]

Virtual IP on the same interface should be enough on network as long as both have OPNsense as default gateway. You will only need a pass rule from one network to the other even if it is on the same interface.

However if it is only a file server there are a lot of good implementations out there. For example:

* samba
* proftpd
* nextcloud

[dcol]

Adding the NIC did something to the license. Even a restore can't get it back now.
Oh well

[fabian]

It is likely bound to some hardware configuration. If you remove the nic from that host and do a restore it may work again.

Please try the solution I provided because it does not need any change to that black box.

If you have a managed switch, you can also use VLANs for separation.

[dcol]

Thanks, but nothing I do retrieves the license. I will contact the vendor Monday and see what they can do.