Patch and steps to get Cisco DNS work in wsl2

cisco_patch.ps1

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################################################################################
#
#               Fix iface metric when starting cisco VPN
#
################################################################################
# Steps
# -----
# 1. First of all, you'll need to get the proper dns server for you, and to do
#    that, You can use nslookup in powersheel (after connected to VPN), or the
#    cmd at step [2]
#
# 2. After this, create/change the /etc/wsl.conf, disabling the resolv conf gen:
#    /etc/wsl.conf
#      [network]
#      generateResolvConf = false
#
# 3. Then, you need to configure the /etc/resolv.conf file in your WSL
#    distribution.
#
#    /etc/resolv.conf
#      # This file was automatically generated by WSL. To stop automatic
#      # generation of this file, add the following entry to /etc/wsl.conf:
#      [network]
#      generateResolvConf = false
#      nameserver 172.19.240.1
#
# 3. Then, after reboot and connect to VPN, use this script everytime.
#
# 4. Check your connection using ping 8.8.8.8
#
#
# See
# ---
# This script is based on
# https://stackoverflow.com/questions/66444822/wsl-2-dns-is-not-working-with-vpn-connection-on-win-10
#
#
# Note
# ----
# In my case, the cisco adapter in the Windows Store, doesn't work anymore.
# Sometimes it disconnects suddenly. This is why I need to use the original VPN
# client for this.
#
# NOTE too that you'll need to enable the script execution for powershell
#
#   >> Get-ExecutionPolicy
#   Restricted
#   >> Set-ExecutionPolicy RemoteSigned
#   >> Get-ExecutionPolicy
#   RemoteSigned

clear
cd ~

Write-Host "[1] Starting patching..."

Write-Host "[2] Getting DHCP server addr"
$DNS=(Get-NetAdapter | Where-Object InterfaceDescription -like "Cisco AnyConnect*" | Get-DnsClientServerAddress).ServerAddresses

Write-Host "[3] Changing iface metric"
Get-NetAdapter | Where-Object {$_.InterfaceDescription -Match "Cisco AnyConnect"} | Set-NetIPInterface -InterfaceMetric 6000

Write-Host "[4] Rebooting wsl"
wsl --shutdown

Write-Host "[5] Done!"