To prioritize a LAN cable over Wi-Fi for accessing network drives, you must adjust the interface metric in your operating system’s network settings. A lower metric value forces the computer to route traffic through the wired connection first. This ensures faster, more stable file transfers and reduces latency when communicating with shared drives on your local area network.
Understanding Network Metrics
When a computer is connected to both a wired Ethernet adapter and a wireless Wi-Fi adapter, it has multiple paths to reach any given destination. The operating system uses a concept called the metric to decide which path to use. Think of the metric as a cost or priority score assigned to each network interface. The interface with the lowest metric value is considered the most efficient route, so the system sends data packets through that connection by default. By default, most modern operating systems automatically assign metrics based on the speed and reliability of the connection. Typically, a wired Gigabit Ethernet connection receives a much lower (better) metric than a Wi-Fi connection because it offers higher bandwidth and lower latency. However, this automatic assignment can sometimes be overridden by other factors, such as driver updates, power-saving settings, or manual configuration errors. If your computer is sending traffic to a network drive via Wi-Fi while an Ethernet cable is plugged in, it usually means the Wi-Fi interface has a lower metric value than the Ethernet interface. To fix this, you need to manually inspect these values and ensure the Ethernet adapter has the lowest number. This process does not disable Wi-Fi; it simply tells the network stack to prefer the wired link for all local traffic, including access to shared folders on NAS devices or other PCs on the same subnet.Adjusting Settings on Windows
Windows provides a straightforward graphical interface to modify these metrics. Start by opening theControl Panel and navigating to Network and Internet, then select Network and Sharing Center. From there, click on Change adapter settings in the left-hand pane to see all your active network connections. You will see icons for your Wi-Fi adapter and your Local Area Connection (Ethernet).
Right-click on the Ethernet adapter and select Properties. In the list of items, find and double-click on Internet Protocol Version 4 (TCP/IPv4). Click the Advanced button at the bottom of the window. Here, you will see a field labeled Automatic metric. Uncheck this box to enable manual entry. Enter a low number, such as 10, into the Interface metric field. Click OK to save the changes, then close all windows.
Next, repeat this process for your Wi-Fi adapter. Open its properties, go to TCP/IPv4 advanced settings, uncheck Automatic metric, and enter a higher number, such as 50 or 100. By setting the Ethernet metric lower than the Wi-Fi metric, you guarantee that any request to access a network drive will travel through the cable first.
Adjusting Settings on macOS
On macOS, the process involves adjusting the service order rather than individual metrics. Open System Preferences and click on Network. You will see a list of services on the left side, such as Wi-Fi and Ethernet. Click the gear icon at the bottom of the list and select Set Service Order. Drag the Ethernet service above the Wi-Fi service in the list. Click OK and then click Apply in the main window. macOS uses this order to determine which interface to use for routing traffic.Verifying the Configuration
After making these changes, verify that the system is using the correct interface. On Windows, open Command Prompt and typeroute print. Look for the routes associated with your local subnet. The entry with the lowest metric should correspond to your Ethernet adapter. You can also ping a known device on the network and check the source IP address to confirm it matches the IP assigned to your wired connection.
If you continue to experience issues, ensure that both adapters are connected to the same router or switch. Mixing networks, such as connecting Ethernet to one router and Wi-Fi to another, can cause routing conflicts. Additionally, some routers have features like "band steering" or "preferred band" that might interfere if not configured correctly, though these typically affect client connections rather than internal routing decisions on the PC itself.
For users experiencing intermittent connectivity during these adjustments, it may be helpful to review logs for packet drops. See how to log intermittent loss of internet for diagnostic steps that can reveal underlying hardware faults.
Frequently Asked Questions
Will changing the metric disconnect my Wi-Fi?
No, changing the metric does not disable the Wi-Fi adapter. It only changes the priority of the routes used by the operating system. Your Wi-Fi connection remains active and available for use if the Ethernet cable is unplugged or fails.How do I know if the change worked?
You can verify the change by pinging a local IP address and checking the source IP in the response. Alternatively, use a tool likenetstat -r on Windows or route get on macOS to see which interface is selected for the destination.
Can I set the metric to zero?
While technically possible on some systems, setting a metric to zero is generally not recommended. Most operating systems require a positive integer. A value between1 and 20 is sufficient for the primary interface, while secondary interfaces should have significantly higher values.