Fixing DNS Issues on Windows Subsystem for Linux (WSL)

The Windows Subsystem for Linux (WSL) is a powerful tool that allows developers to run a Linux environment directly on Windows without the overhead of a traditional virtual machine or dual-boot setup. However, like any system, it’s not without its quirks. One of the common issues users encounter is related to Domain Name System (DNS) resolution. In this article, we’ll explore how to fix DNS issues on WSL.

Understanding the Problem

DNS issues in WSL typically manifest as an inability to connect to the internet or access specific websites. This is because DNS, which translates human-readable domain names into IP addresses that computers can understand, isn’t functioning correctly. The root of the problem often lies in the /etc/resolv.conf file, which WSL uses to determine which DNS servers to use.

Solution 1: Update the DNS Server Address in /etc/resolv.conf

The first solution involves directly editing the /etc/resolv.conf file to point to a different DNS server. Here’s how you can do it:

1. Open the WSL terminal.
2. Use a text editor to open the /etc/resolv.conf file. For example, you can use nano by typing nano /etc/resolv.conf.
3. In the file, you’ll see a line that looks like this: nameserver 172.22.192.1. This is the default DNS server address. Change it to a working DNS server address, such as 1.1.1.1 (Cloudflare DNS) or 8.8.8.8 (Google DNS).
4. Save the changes and exit the text editor. In nano, you can do this by pressing Ctrl+X, then Y, then Enter.
5. Restart WSL and check if the DNS issue is resolved.

Solution 2: Disable the Generation of /etc/resolv.conf

If the first solution doesn’t work, you can try disabling the automatic generation of the /etc/resolv.conf file. This can be done by adding certain lines to the /etc/wsl.conf file. Here’s how:

1. Open the WSL terminal.
2. Use a text editor to create or edit the /etc/wsl.conf file. For example, nano /etc/wsl.conf.
3. Add the following lines to the file:

   [network]
   generateResolvConf = false

   This tells WSL not to generate a new /etc/resolv.conf file every time it starts.
4. Save the changes and exit the text editor.
5. Restart WSL and check if the DNS issue is resolved.

Solution 3: Check Firewall Settings

Sometimes, the issue might be due to the Windows Firewall blocking DNS requests from the WSL virtual machine. Here’s how to check and fix this:

1. Open the Windows Firewall settings.
2. Check if the firewall is blocking DNS requests from WSL. If necessary, whitelist WSL or change the firewall settings to allow DNS requests from WSL.
3. Restart WSL and check if the DNS issue is resolved.

Solution 4: Change the Network Profile to Private

If you’re on a safe network, changing your network profile to Private can sometimes resolve DNS issues in WSL. Here’s how to do it:

1. Open the Windows network settings.
2. Change the network profile to Private.
3. Restart WSL and check if the DNS issue is resolved.

Conclusion

DNS issues in WSL can be frustrating, but they’re usually not too difficult to fix. With the solutions provided above, you should be able to resolve most DNS problems you encounter. Remember, if you’re using a VPN, it may interfere with DNS resolution in WSL. If none of the above solutions work, try disconnecting the VPN and see if the DNS issue persists.

If you’re still having trouble, it may be worth reaching out to the Microsoft WSL community for additional help. They’re a knowledgeable and helpful bunch who are always willing to assist with WSL issues.