My local IP in on Windows 10 changed randomly?

Question

My local IP recently changed from 192.168.1.230 to 192.168.1.156

I would not have noticed this if it weren't for the fact I run a PLEX media server on my home computer and the change of the IP killed my Port Forwarding settings already assigned in the router to enable the server to run properly.

Is there anything that could have caused this? I'm not new to computers remotely. But I'm no pro with networking matters. But this very odd / disconcerting and I can't seem to figure out what could have changed it.

Is there anyone who would know why this is?

Answer 1

Have you configured your router to assign your computer a specific IP address?

If not, then your IP address most likely changed because a DHCP lease expired. One of the uses of DHCP – the Dynamic Host Configuration Protocol – is automatically assigning IP addresses to devices on the network. Addresses are "leased" for a length of time, and your computer will request a new lease once the one it currently holds expires.

If you're using ISP-provided equipment, it will almost certainly have come with DHCP enabled, as it enables zero-effort set-up, and unless you specifically configure your router to assign your computer a specific IP address, you will get a random address from the pool the router has been configured to use. In your case, this pool is probably 192.168.1.0/24.

To set your router to assign you a specific IP address, look for something labelled DHCP Settings or DHCP Reservation in the router's administration interface. You will most likely then be prompted to enter a MAC address and the desired IP address. Your router may display the MAC addresses of currently-connected devices, or you may have to enter it manually. To find your MAC address, enter ipconfig /all into the command prompt and look for "Ethernet adapter" sections:

The value marked in red in this image is the one you want (although I've censored three octets of mine).