Windows Laptop Not Querying Local DNS Server with WSL

Introduction

In this article, we will discuss a common issue faced by Windows laptop users who also use Linux on their machines via Windows Subsystem for Linux (WSL). Specifically, we will look at why a local PowerDNS server on a Linux box might not be queryable from a Windows laptop, even though the DNS server can be accessed using tools like dig and ping within the WSL environment.

Understanding the Issue

When you run dig @mainprobitas within WSL, you might get the expected IP address as a response. However, when you try to access the same DNS server from your Windows laptop using the same command, you might not get a response. This issue arises due to the way that WSL handles network traffic.

By default, WSL uses a NAT (Network Address Translation) network stack, which means that the IP address of the WSL environment is different from the IP address of the Windows host. This can cause issues when trying to access network services hosted on the Windows host from within WSL, or vice versa.

Solutions

Use the Host's IP Address

One solution to this issue is to use the IP address of the Windows host instead of the name of the WSL environment. You can find the IP address of your Windows host by running the command ipconfig in the Command Prompt.

Change WSL's Network Stack

Another solution is to change WSL's network stack from NAT to bridge mode. This will allow WSL to use the same network stack as the Windows host, which can help resolve issues with network traffic between the two environments.

To change WSL's network stack to bridge mode, follow these steps:

1. Open the Command Prompt as an administrator.
2. Run the command wsl --set-default-version 2 to ensure that WSL is using version 2.
3. Create a new virtual Ethernet switch by running the command wsl --veth create --name wsl-switch.
4. Set WSL to use the new virtual Ethernet switch by running the command wsl --set-net-name wsl-switch.
5. Restart your Windows laptop.

Configure PowerDNS to Listen on All Interfaces

By default, PowerDNS listens only on the loopback interface (127.0.0.1). To allow PowerDNS to be accessed from outside the WSL environment, you need to configure it to listen on all interfaces.

To do this, open the PowerDNS configuration file (/etc/powerdns/pdns.conf) and add the following line:

launch=gmysql

This will configure PowerDNS to use the gmysql backend, which listens on all interfaces.

In this article, we have discussed why a local PowerDNS server on a Linux box might not be queryable from a Windows laptop when using WSL, and provided some solutions to resolve the issue. By using the IP address of the Windows host, changing WSL's network stack to bridge mode, or configuring PowerDNS to listen on all interfaces, you can ensure that your Windows laptop can access the PowerDNS server hosted on your Linux box.

References

• WSL Networking
• WSL 2 Networking
• PowerDNS Configuration Reference