www/blog.bryanroessler.com/_posts/2021-02-18-external-wsl2-access-ubuntu-20-w-powershell.md

---

layout: post title: 'Restoring external (remote) WSL2 access' date: 2021-02-18 11:01

tags: [windows, wsl, wsl2, linux, ssh, firewall, ip, ifconfig, powershell]

Cannot access WSL2 instances remotely

If you rely on external (remote) access to the Windows Subsystem for Linux (WSL2) you may have noticed that your manual port forwards have suddenly stopped working. Microsoft has started issuing WSL2 instances a randomized IP address on startup, which makes it difficult to reliably access services hosted in the Linux subsystem. However, it's still possible to probe the WSL2 instance on startup and open the appropriate ports using Powershell.

Most existing solutions rely on legacy ifconfig, which has been deprecated in Ubuntu 20.04 (available in WSL2 via an in-place do-release-upgrade) in favor of ip:

Solution

Steps:

1. Download or copy-paste the following Powershell script to a local file:

{% highlight powershell %} {% insert_git_code https://git.bryanroessler.com/bryan/scripts/raw/master/powershell/wsl2-firewall-rules.ps1 %} {% endhighlight %}

1. Edit the port list to add any additional WSL2 ports you wish to expose

2. Create a startup new task in the Windows Task Scheduler:

   • Name: 'WSL2-Bypass'
   • Triggers: At log on, for any user
   • Actions:
     • Program/Script: powershell
     • Add Arguments: -ExecutionPolicy Bypass C:\Users\Bryan\Path\To\wsl2-firewall-rules.ps1

3. Save the task and run it

Troubleshooting

• Make sure that you have already made the appropriate firewall changes within the instance itself.
• Make sure that your service is running.
• Try probing for the IP address manually and connecting to the service from the Windows machine.

Enjoy unfettered remote access to your WSL2 instances again!