iamqiz/bash-wsl2-host

Bash script to automatically update your Windows hosts file with the WSL2 VM IP address

wsl2hosts

中文文档

Bash script to automatically update your Windows hosts file with the WSL2 VM IP address and name.

Dependencies:

gerardog/gsudo: gsudo - a sudo for Windows https://github.com/gerardog/gsudo

gsudo is a sudo equivalent for Windows, with a similar user-experience as the original Unix/Linux sudo. Allows to run commands with elevated permissions, or to elevate the current shell, in the current console window or a new one.

Usage:

1. Download gsudo in Windows and install. For example, I did portable installation in %USERPROFILE%\gsudo\

2. Add this script to ~/.bashrc and
   Define your dns name in _wsl_ssh_ip_name variable.
   Add location from gsudo and WindowsPowerShell to PATH environment variable in the script.

#!/bin/bash

# adjust this paths to your environment
export PATH=/mnt/c/Users/your-USERNAME/gsudo/x64/:$PATH
export PATH=/mnt/c/Windows/System32/WindowsPowerShell/v1.0/:$PATH

change_wsl_ssh_ip(){
  # define your dns name
  _wsl_ssh_ip_name="ubuntu2004.wsl"

  # set windows hosts file path
  _wslhosts=/mnt/c/Windows/System32/drivers/etc/hosts
  _winhosts='C:\Windows\System32\drivers\etc\hosts'

  # get wsl real ip and ignore wsl-vpnkit
  _wsl_ssh_ip_addr=$(ip -4 addr show "eth0" | grep -oP '(?<=inet\s)\d+(\.\d+){3}' | head -1)
  echo "wsl ssh ip addr:[$_wsl_ssh_ip_addr]"

  # get current ip from windows hosts
  _win_ssh_ip_addr=$(grep -oP "\d+(\.\d+){3}(?=\s*$_wsl_ssh_ip_name)" $_wslhosts)
  echo "win ssh ip addr:[$_win_ssh_ip_addr]"

  # check if ip exists or diff, then modify
  if [[ "$_win_ssh_ip_addr" == "" ]]
  then
    echo "ssh ip is missing, adding to windows hosts"
    gsudo powershell.exe -Command "echo '' '$_wsl_ssh_ip_addr  $_wsl_ssh_ip_name' | out-file -encoding ASCII $_winhosts -append"
  else
    if [[ "$_win_ssh_ip_addr" != "$_wsl_ssh_ip_addr" ]]
    then
      echo "ssh ip diff, modifying windows hosts"
      gsudo powershell.exe -Command "(gc $_winhosts) -replace '$_win_ssh_ip_addr', '$_wsl_ssh_ip_addr' | out-file -encoding ASCII $_winhosts"
    else
      echo "ssh ip ok"
    fi
  fi

  # resulting windows hosts
  echo "now $_wsl_ssh_ip_name 's ip is:"
  grep "$_wsl_ssh_ip_name" $_wslhosts
}

# run the function
change_wsl_ssh_ip

3. Now shutdown and restart your wsl to check whether the bash script works.

C:\>wsl --shutdown

4. Finally check the stdout that the content of the Windows hosts file has changed.

...
123.45.67.89  ubuntu2004.wsl 
...

bash-wsl2-host's Issues

Script empties the hole hosts file :-O

Nice idea, but I'm having trouble with the script. I'm located behind a proxy and VPN, therefore I use wsl-vpnkit. There was no entry in the hosts file for the running distribution and the Bash-wsl2-host script stuck during the Windows PowerShell process and empties the hole hosts file, that's not good.