WSL Mirrored Network Mode Configuration Guide

WSL 2.6.0 networking upgrade configuration guide
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Version Requirements

Current version status:

  • Latest stable: 2.5.9 (known networking issues)
  • Recommended version: 2.6.0 preview (full mirrored mode support)

Mode Comparison Analysis

Feature bridge mode (deprecated) mirrored mode (recommended)
Protocol architecture Dual-stack Shared stack
IP address allocation Independent IP (Windows + WSL) Shared host IP
Port resources Separate Shared ports (conflict-avoidance required)
Network performance Relatively heavy Lightweight & efficient
Configuration complexity Simple Requires deep firewall policy setup

Standard Configuration Steps

1. Network Mode Settings

Configure the base mode via WSL Settings app:

  1. Open the Settings app
  2. Select the Network tab
  3. Set network mode to Mirrored
  4. Apply the configuration and restart WSL

2. Firewall Policy Configuration

Run the complete policy configuration via PowerShell:

# Define the WSL VM GUID
$wslGuid = '{40E0AC32-46A5-438A-A0B2-2B479E8F2E90}'

# Configure firewall policies (execute in order)
Set-NetFirewallHyperVVMSetting -Name $wslGuid -Enabled True
Set-NetFirewallHyperVVMSetting -Name $wslGuid -DefaultInboundAction Allow
Set-NetFirewallHyperVVMSetting -Name $wslGuid -DefaultOutboundAction Allow
Set-NetFirewallHyperVVMSetting -Name $wslGuid -LoopbackEnabled True
Set-NetFirewallHyperVVMSetting -Name $wslGuid -AllowHostPolicyMerge True

# Verify configuration results
Get-NetFirewallHyperVVMSetting -Name $wslGuid

3. Port Mapping Validation

# Example: Check port 80 usage
Get-NetTCPConnection -LocalPort 80

Common Issue Troubleshooting

Issue 1: External Connections Fail

  • Check step: All fields returned by Get-NetFirewallHyperVVMSetting should be True/Allow
  • Solution: Re-run the firewall policy configuration commands in order

Issue 2: Port Conflicts

  • Check method: Use netstat -ano to view port usage
  • Handling advice: Prefer to release ports occupied by Windows, or change the listening port in the WSL service

Validation Steps

  1. Start your WSL service (e.g., Nginx/Apache)
  2. Access from Windows host: http://localhost:<port>
  3. Access from LAN devices: http://<host-ip>:<port>

References

  1. WSL Official Networking Docs
  2. WSL 2.6.0 Release Notes