DnsSwitcher

Русская версия

Portable Windows utility for fast DNS profile switching with a shared core, CLI, desktop UI, tray client, and built-in diagnostics.

Overview

DnsSwitcher is a Windows-first project for managing DNS profiles without scattering logic across multiple apps.
One shared core drives three clients:

• DnsSwitcher.Cli for commands and automation
• DnsSwitcher.Ui for regular desktop usage
• DnsSwitcher.Tray for instant switching from the system tray

The project also includes a privileged Windows agent so UI and tray can change DNS without requiring elevation on every action.

Features

• Portable data layout stored next to the app
• DNS profile storage in profiles.json
• Fast apply/reset workflow
• Current DNS status detection
• Default network adapter selection
• DNS diagnostics by domain
• Site accessibility diagnostics by URL
• Multi-profile DNS benchmark with best-profile selection and history storage
• Optional DNS health failover monitor
• Optional Split DNS through Windows NRPT rules
• Interactive console mode for users who prefer a console menu
• Desktop UI for standard usage
• Tray client for fast switching
• Automatic language selection from the system with manual override
• Automatic light/dark UI theme from the system with manual override
• UI profile create/edit/delete plus import/export
• Agent/service model for privileged DNS operations
• File logging and graceful error handling

Architecture

DnsSwitcher.Core
  Models, validation, services, selection logic, DNS/site test orchestration

DnsSwitcher.Infrastructure.Windows
  Windows DNS management, adapter discovery, config storage, logging, IPC client

DnsSwitcher.Agent.Windows
  Privileged Windows Service / agent over Named Pipes

DnsSwitcher.Cli
  Command-line and interactive console client

DnsSwitcher.Ui
  WPF desktop client

DnsSwitcher.Tray
  WinForms tray client

DnsSwitcher.Tests
  Unit tests for config, validation, adapter selection, matching, and diagnostics

Runtime flow

• CLI, UI, and Tray use the same shared core.
• Privileged DNS changes go through DnsSwitcher.Agent.Windows when available.
• If the agent is unavailable, direct fallback is possible only from an elevated process.
• Config and logs are portable and live under the app directory.

Stack

• C# / .NET 10
• WPF for desktop UI
• WinForms NotifyIcon for tray
• Windows Service hosting for the agent
• Named Pipes for IPC
• xUnit for unit tests

Projects

• src/DnsSwitcher.Core
• src/DnsSwitcher.Infrastructure.Windows
• src/DnsSwitcher.Contracts
• src/DnsSwitcher.Agent.Windows
• src/DnsSwitcher.Cli
• src/DnsSwitcher.Ui
• src/DnsSwitcher.Tray
• tests/DnsSwitcher.Tests

Portable layout

data/
  config/
    app-preferences.json
    dns-benchmark-history.json
    dns-health-settings.json
    dns-health-state.json
    profiles.json
    split-dns-rules.json
    tray-settings.json
    ui-settings.json
  logs/
    dns-switcher.log

During development, clients started from this repository share the solution-level data/config/profiles.json path when available.

CLI

Run help:

dotnet run --project src/DnsSwitcher.Cli -- help

Main commands:

dns-switcher profiles
dns-switcher adapters
dns-switcher status
dns-switcher current
dns-switcher apply <profile-id>
dns-switcher reset
dns-switcher test
dns-switcher test-sites
dns-switcher benchmark
dns-switcher health <status|enable|disable|check|chain|fallback|action|domains>
dns-switcher split-dns <status|enable|disable|list|add|remove|update|enable-rule|disable-rule|test|apply|reset>
dns-switcher validate-config
dns-switcher service <install|reinstall|uninstall|start|stop|status>

Global options:

--adapter <id|name>
--config <path>

Interactive console mode:

dotnet run --project src/DnsSwitcher.Cli

UI

DnsSwitcher.Ui provides:

• profile list
• adapter selection
• current DNS status block
• apply/reset actions
• DNS test
• site test
• profile benchmark
• DNS health check and health monitor toggle
• DNS Health Failover settings window with thresholds, cooldown, action mode, fallback profile, failover chain, test domains, and expected IPs
• Split DNS rules editor with add/edit/delete/enable/disable/test/apply/reset
• Agent manager window for install/reinstall/start/stop/uninstall/status
• create/edit/delete profiles
• import/export profiles
• remember last selected adapter and profile
• optional continue-in-tray behavior on window close
• open config/log folders
• optional Windows autostart for the tray client
• automatic language/theme from the system
• manual language selection
• manual theme selection
• background refresh for config and external state changes

Screenshots

Screenshots are intentionally not included in v1.4.1 yet. UI and tray screenshots can be added later without changing the shipped functionality.

Tray

DnsSwitcher.Tray provides:

• current state in tooltip/menu
• enable DNS
• disable DNS
• switch next profile
• profile list
• DNS and site tests
• profile benchmark
• DNS health check and health monitor toggle
• Split DNS status/apply/reset
• Agent status/start/stop/reinstall submenu
• persistent tray settings
• open UI action
• shared app language preference
• shared app theme preference

Diagnostics

Three diagnostics are built in:

• test DNS resolution check using testDomains
• test-sites Site accessibility check using testUrls with staged: DNS -> TCP -> TLS -> HTTP probing
• benchmark sequentially applies switchable DNS profiles, tests domains, compares latency, stores recent results, and restores the original DNS settings
• health optional background health checks with failover actions
• split-dns Windows NRPT-based per-namespace DNS routing

These are kept separate on purpose so DNS issues, HTTP/connectivity issues, and profile comparison are not mixed into one unclear result.

Example config

Full example: docs/profiles.example.json

{
  "version": 1,
  "activeProfileId": null,
  "profiles": [
    {
      "id": "cloudflare",
      "name": "Cloudflare",
      "mode": "static",
      "ipv4": ["1.1.1.1", "1.0.0.1"],
      "ipv6": ["2606:4700:4700::1111", "2606:4700:4700::1001"],
      "tags": ["public", "general"],
      "testDomains": ["cloudflare.com", "openai.com"],
      "testUrls": ["https://cloudflare.com/", "https://openai.com/"]
    },
    {
      "id": "dhcp",
      "name": "Automatic DNS",
      "mode": "dhcp",
      "ipv4": [],
      "ipv6": []
    }
  ]
}

Build

Environment setup (Windows, PowerShell):

powershell -NoProfile -ExecutionPolicy Bypass -File .\scripts\dev-setup.ps1

Build and test:

dotnet build DnsSwitcher.sln -c Release
dotnet test tests\DnsSwitcher.Tests\DnsSwitcher.Tests.csproj -c Release

Release Build

Create a framework-dependent Windows release package:

powershell -NoProfile -ExecutionPolicy Bypass -File .\scripts\publish-release.ps1

The release archive is written under:

artifacts/release/v1.4.1/

Build installer:

.\installer\build-installer.ps1 -Version 1.4.1 -Runtime win-x64

Release docs:

• PORTABLE_RELEASE.md
• SERVICE_INSTALL.md
• INSTALLER_RELEASE.md
• DNS_HEALTH_FAILOVER.md
• SPLIT_DNS.md
• STORE_READINESS.md
• docs/ipc-integration-tests.md

Limitations

• Windows-only
• DNS changes still depend on Windows networking APIs and command-line tools
• Agent/service installation requires administrator rights
• Split DNS uses Windows NRPT and can be bypassed by apps using their own DNS/DoH stack
• Without screenshots, portfolio presentation is documentation-first in v1.4.1
• CLI is still not fully localized
• Private DNS profiles should stay in local ignored config files and must not be committed

Portfolio notes

This project demonstrates:

• layered architecture with a shared core
• separation of domain logic from platform-specific infrastructure
• multiple clients over one core
• Windows service + IPC integration
• validation, diagnostics, and error handling
• iterative delivery from MVPs to a release-ready structure

Changelog

See CHANGELOG.md.