WSL install and using it with proxy

October 7th, 2022 in programming
Last updated on: February 15th, 2023

WSL install instruction from MS.

dism.exe /online /enable-feature /featurename:Microsoft-Windows-Subsystem-Linux /all /norestart
List all distribution online
wsl --list --online // list out available distribution
wsl --set-default-version 1 // using WSL1 because I have some issue on virtual network with WSL2
wsl --install -d Ubuntu // install Ubuntu WSL
wsl -d Ubuntu // open WSL

If your PC is behind firewall, when you try to install/update package, following error shall occur.

user@usergrp:~$ sudo apt update
Err:1 http://archive.ubuntu.com/ubuntu focal InRelease
  Connection failed [IP: 185.125.190.39 80]
Err:2 http://archive.ubuntu.com/ubuntu focal-updates InRelease
  Connection failed [IP: 91.189.91.39 80]
Err:3 http://security.ubuntu.com/ubuntu focal-security InRelease
  Connection failed [IP: 91.189.91.39 80]
Err:4 http://archive.ubuntu.com/ubuntu focal-backports InRelease
  Connection failed [IP: 185.125.190.39 80]
Reading package lists... Done
Building dependency tree
Reading state information... Done
277 packages can be upgraded. Run 'apt list --upgradable' to see them.
W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/focal/InRelease  Connection failed [IP: 185.125.190.39 80]
W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/focal-updates/InRelease  Connection failed [IP: 91.189.91.39 80]
W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/focal-backports/InRelease  Connection failed [IP: 185.125.190.39 80]
W: Failed to fetch http://security.ubuntu.com/ubuntu/dists/focal-security/InRelease  Connection failed [IP: 91.189.91.39 80]
W: Some index files failed to download. They have been ignored, or old ones used instead.

to fix above issues, following below step.

sudo vim ~/.bashrc
Add following at the end of file:
export http_proxy=http://<address>:<port>
sudo visudo
Add following line after line “Defaults env_reset”
Defaults env_keep = "http_proxy"

Things should be able to run smoothly now.

user@usergrp:~$ sudo apt update
Get:1 http://security.ubuntu.com/ubuntu focal-security InRelease [114 kB]
Hit:2 http://archive.ubuntu.com/ubuntu focal InRelease
Hit:3 http://archive.ubuntu.com/ubuntu focal-updates InRelease
Get:4 http://archive.ubuntu.com/ubuntu focal-backports InRelease [108 kB]
Fetched 222 kB in 10s (21.2 kB/s)  
Reading package lists... Done
Building dependency tree       
Reading state information... Done
275 packages can be upgraded. Run 'apt list --upgradable' to see them.

If adding proxy environment variables still not work, then we can configure the proxy setting directly to apt configuration.
Set the content of apt config file /etc/apt/apt.conf as below: Acquire::http::Proxy "http://<proxy-server>:<port>";
Acquire::https::Proxy "https://<proxy-server>:<port>";