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Have any of your devices ever displayed an error message pertaining to an IP address conflict? If so, you probably found yourself unable to connect to the Internet, either because you simply don’t have access or the connection has just been rendered unusable.
Although it’s not something that commonly occurs, IP address conflicts are a very real issue and can very much inconvenience the user. When two or more IP addresses conflict, the result can be one or more computers or devices that have been rendered completely useless in terms of network connectivity. Fortunately, there are ways to resolve the issue when conflicts occur.
What is an IP conflict?
IP conflicts occur when two or more computers or devices (like a tablet) in the same network end up being assigned the same IP address. An IP (Internet Protocol) address is your computer’s unique identifier, comprised of a string of numbers, such as 192.168.8.4. Without one, you can’t connect to the network. Usually a sort of warning or error message will pop up, alerting you of the problem. Sometimes these issues resolve themselves, but that’s not always the case.
Usually, IP address conflicts occur on a LAN (local area network), although they may also be seen between multiple devices connected to the Internet. Any device that has an IP address could potentially have a conflict with another device.
An IP address can be either static or dynamic. A static IP address never changes and is manually assigned. Dynamic IP addresses, on the other hand, are only temporary and a new one is assigned every time your computer or device connects to the Internet or your router.
Conflicts can happen with both static and dynamic IP addresses, although they are less likely to occur with static addresses today, because typically a DHCP (dynamic host configuration protocol) server, which is built into most routers, is used to manage and assign IP addresses. DHCP servers have a pool of IP addresses, called a scope, and from that pool addresses are assigned to devices in response to a system request for an IP address.
Why Does It Happen?
An IP conflict can happen for various reasons, but a classic example is when two or more systems are assigned the same static IP address. This doesn’t happen as much now thanks to DHCP servers. However, if you have more than one DHCP server running (which you shouldn’t), similarly configured servers may hand out identical address to multiple devices.
If you have another device that facilitates a network connection, it may have an embedded DHCP server that is turned on by default. In this case, going in and switching off the server will resolve the issue.
An ISP may also assign multiple customers the same address. If a device is set up with multiple network adapters, then it could potentially experience an IP address conflict with itself.
A conflict may also occur if a device originally connected to one network enters standby mode and later comes back on, but connected to a different network with a device that has the same IP address. This could happen with a work laptop being brought home, or even when traveling with a laptop or another device.
How Do You Resolve It?
IP conflicts sometimes just work themselves out, but that could take a while, if it even happens at all. Resolving the issue could be as simple as just restarting the router. If every device in the network was assigned dynamic IP addresses, the issue should be fixed as the router reboots and re-assigns IP addresses to every device in the network.
Another way to fix this issue (at least on Windows systems) is to release the IP address via the command prompt. Open up the command prompt (you can do this by going to your start menu and searching for ‘command prompt’) and type “ipconfig /release” in the window, then press enter. The DHCP server will then assign a new IP address to your computer.
If that doesn’t work, you will need to identify the conflicting addresses in the router’s administrative dashboard and either manually assign new IP addresses, or configure the devices to automatically obtain IP addresses.
Finally, if none of this works or you encounter this frequently, your router may have a faulty DHCP server. In that case, you would have to upgrade the firmware. You can usually get a firmware update from the manufacturer’s website, which can be installed manually.
As we connect more and more devices to our networks and the Internet, the likelihood of experiencing some sort of IP conflict goes up. While it isn’t something that one can expect to encounter every day (and if you do deal with this frequently, you should upgrade your firmware), it is good to understand the issue and know what steps to take to resolve it.
Have you ever encountered an IP conflict? Do you know what caused it? How did you deal with it? Leave a comment below and tell me about it!
Image credits: DHCP by Rodrigozanatta via Wikimedia Commons