GNS3 MCP Server

Model Context Protocol (MCP) server for GNS3 network lab automation. Control GNS3 projects, nodes, and device consoles through Claude Desktop or any MCP-compatible client.

Version: 0.49.0

Features

• 15 Tools: CRUD-style GNS3 automation (v0.47.0: 53% consolidation from 32 tools)

• 25 Resources: Read-only data access (projects, nodes, links, sessions, topology reports)

• CRUD Pattern: Consolidated tools with action parameters (project(action="open"), node(action="create"), etc.)

• Batch Operations: Console and SSH operations use batch-only APIs for atomic execution

• Wildcard Support: Node operations support patterns (*, Router*, R[123], JSON arrays)

• Project Management: Create, open, close GNS3 projects

• Node Control: Start/stop/restart nodes with wildcard patterns and parallel execution

• Console Access: Telnet console automation with pattern matching and grep filtering

• SSH Automation: Network device automation via Netmiko (200+ device types)

• Network Topology: Batch connect/disconnect links, create drawings, export diagrams

• Docker Integration: Configure container networks, read/write files

• Tool Discovery: search_tools() with category/capability/resource filtering

• Claude Desktop Support: All resources accessible via tools (query_resource, list_projects, list_nodes, get_topology)

• Security: API key authentication (HTTP mode), service privilege isolation, HTTPS support

Installation

Supported Platform: Windows only

Quick Start (Claude Code - Recommended)

Prerequisites:

• Windows 10/11

• GNS3 server running and accessible

• Claude Code installed

• uv package manager (for uvx): Install with pip install uv or download from https://github.com/astral-sh/uv

Option 1: Using uvx (Recommended - Faster)

# Single command - no .env file needed!
claude mcp add --transport stdio gns3-mcp `
  --env GNS3_HOST=192.168.1.20 `
  --env GNS3_PORT=80 `
  --env GNS3_USER=admin `
  --env GNS3_PASSWORD=your-password `
  --scope user `
  -- uvx gns3-mcp@latest

# Verify installation
claude mcp get gns3-mcp
# Should show: Status: ✓ Connected

Option 2: Using pip (Traditional)

# Step 1: Install package
pip install gns3-mcp

# Step 2: Add to Claude Code with credentials
claude mcp add --transport stdio gns3-mcp `
  --env GNS3_HOST=192.168.1.20 `
  --env GNS3_PORT=80 `
  --env GNS3_USER=admin `
  --env GNS3_PASSWORD=your-password `
  --scope user `
  -- gns3-mcp

# Step 3: Verify installation
claude mcp get gns3-mcp
# Should show: Status: ✓ Connected

Why uvx? 10-100× faster than pip, automatic dependency isolation, no venv management needed.

Installation by Editor

Claude Code Setup

STDIO Mode (Recommended)

STDIO mode is more secure - no HTTP service, no authentication needed, runs only when Claude Code is active.

Using uvx (Recommended):

# 1. Install uv (one-time setup)
pip install uv

# 2. Create .env file
@"
GNS3_HOST=192.168.1.20
GNS3_PORT=80
GNS3_USER=admin
GNS3_PASSWORD=your-password
"@ | Out-File -FilePath .env -Encoding ASCII

# 3. Add to Claude Code
claude mcp add --transport stdio gns3-mcp --scope user -- uvx gns3-mcp@latest

# 4. Verify
claude mcp get gns3-mcp

Using pip:

# 1. Install package globally
pip install gns3-mcp

# 2. Create .env file in project directory
@"
GNS3_HOST=192.168.1.20
GNS3_PORT=80
GNS3_USER=admin
GNS3_PASSWORD=your-password
"@ | Out-File -FilePath .env -Encoding ASCII

# 3. Add to Claude Code
claude mcp add --transport stdio gns3-mcp --scope user -- gns3-mcp

# 4. Verify
claude mcp get gns3-mcp
# Should show: Status: ✓ Connected

Environment Variables:

Claude Desktop Setup

Installation:

1. Download the latest .mcpb package:

   • From Releases

   • Or build locally: just build (creates mcp-server\mcp-server.mcpb)

2. Install by double-clicking the .mcpb file

3. Configure credentials in Claude Desktop:

   • Open Claude Desktop

   • Go to Settings > Developer > Edit Config

   • Find gns3-mcp server

   • Add environment variables:

     {
       "GNS3_HOST": "192.168.1.20",
       "GNS3_PORT": "80",
       "GNS3_USER": "admin",
       "GNS3_PASSWORD": "your-password"
     }

4. Restart Claude Desktop

5. Check logs if issues occur:

   C:\Users\<username>\AppData\Roaming\Claude\logs\mcp-server-GNS3 Lab Controller.log

Cursor Setup

Configuration File Location:

• Project-specific: .cursor\mcp.json (in project directory)

• Global: %USERPROFILE%\.cursor\mcp.json

Using uvx (Recommended):

1. Install uv: pip install uv

2. Create/edit .cursor\mcp.json:

{
  "mcpServers": {
    "gns3-mcp": {
      "command": "uvx",
      "args": ["gns3-mcp@latest"],
      "env": {
        "GNS3_HOST": "192.168.1.20",
        "GNS3_PORT": "80",
        "GNS3_USER": "admin",
        "GNS3_PASSWORD": "your-password"
      }
    }
  }
}

Using pip:

1. Install package: pip install gns3-mcp

2. Create/edit .cursor\mcp.json:

{
  "mcpServers": {
    "gns3-mcp": {
      "command": "gns3-mcp",
      "args": [],
      "env": {
        "GNS3_HOST": "192.168.1.20",
        "GNS3_PORT": "80",
        "GNS3_USER": "admin",
        "GNS3_PASSWORD": "your-password"
      }
    }
  }
}

3. Restart Cursor

Windsurf Setup

Configuration File Location: %USERPROFILE%\.codeium\windsurf\mcp_config.json

Using uvx (Recommended):

1. Install uv: pip install uv

2. Create/edit mcp_config.json:

{
  "mcpServers": {
    "gns3-mcp": {
      "command": "uvx",
      "args": ["gns3-mcp@latest"],
      "env": {
        "GNS3_HOST": "192.168.1.20",
        "GNS3_PORT": "80",
        "GNS3_USER": "admin",
        "GNS3_PASSWORD": "your-password"
      }
    }
  }
}

Using pip:

1. Install package: pip install gns3-mcp

2. Create/edit mcp_config.json:

{
  "mcpServers": {
    "gns3-mcp": {
      "command": "gns3-mcp",
      "args": [],
      "env": {
        "GNS3_HOST": "192.168.1.20",
        "GNS3_PORT": "80",
        "GNS3_USER": "admin",
        "GNS3_PASSWORD": "your-password"
      }
    }
  }
}

3. Restart Windsurf

Note: Cursor and Windsurf use identical configuration formats.

Troubleshooting

Connection Issues:

# Test GNS3 server connectivity
curl http://192.168.1.20:80/v3/projects

# Check Claude Code MCP status
claude mcp get gns3-mcp

# View detailed logs (Claude Code)
# Check console output when running commands

Common Issues:

• "gns3-mcp not found": Ensure package is installed (pip list | findstr gns3-mcp)

• "Connection refused": Verify GNS3 server is running and accessible

• "Authentication failed": Check credentials in .env file

• "Socket is closed": SSH session expired, reconnect automatically on next command

For Claude Desktop issues: Check logs at:

C:\Users\<username>\AppData\Roaming\Claude\logs\mcp-server-GNS3 Lab Controller.log

Advanced Setup

HTTP Mode Configuration

HTTP mode requires a persistent service and API key authentication. Only use if you need the service always running or network access from other machines.

Prerequisites:

• .env file with GNS3 credentials

• API key for authentication

Setup:

1. Add to .env:

   # Generate with: python -c "import secrets; print(secrets.token_urlsafe(32))"
   MCP_API_KEY=your-random-token-here

2. Configure Claude Code:

   claude mcp add --transport http gns3-mcp http://127.0.0.1:8100/mcp/ --scope user`
     --header "MCP_API_KEY: your-random-token-here"

3. Start server (in separate terminal):

   gns3-mcp --transport http --http-port 8100

Note: If MCP_API_KEY is missing from .env, it will be auto-generated on first start and automatically saved to .env for persistence.

Windows Service Deployment

Run MCP server as a Windows service with WinSW and uvx (for HTTP mode).

📖 See PORTABLE_SETUP.md for detailed instructions.

Quick Setup:

# 1. Install uv (if not already installed)
pip install uv

# 2. Set environment variables from .env (requires Administrator)
.\set-env-vars.ps1

# 3. Install and start service (requires Administrator)
.\server.cmd install

Service Management:

# Check status
.\server.cmd status

# Start/stop/restart
.\server.cmd start
.\server.cmd stop
.\server.cmd restart

# After code updates
.\server.cmd reinstall        # Reinstall service

# Remove service
.\server.cmd uninstall

# Development mode (direct run, no service)
.\server.cmd run

Key Features:

• ✅ Portable: Works from any folder location (no hardcoded paths)

• ✅ No venv: Uses uvx for automatic isolation

• ✅ Secure: Credentials in Windows environment variables

• ✅ Simple: Automated setup with PowerShell script

• User: GNS3MCPService (low privilege, optional)

• Startup: Automatic

• Logs: mcp-http-server.log and GNS3-MCP-HTTP.wrapper.log

Manual Installation from Source

Requirements:

• Python ≥ 3.10

• GNS3 Server v3.x running and accessible

Setup:

# Install dependencies
pip install -r requirements.txt

# Create .env file
@"
GNS3_HOST=192.168.1.20
GNS3_PORT=80
GNS3_USER=admin
GNS3_PASSWORD=your-password
"@ | Out-File -FilePath .env -Encoding ASCII

# Run directly (STDIO mode - no authentication)
python gns3_mcp\cli.py --host 192.168.1.20 --port 80 --username admin --password your-password

# Or add to Claude Code (project-scoped)
claude mcp add --transport stdio gns3-mcp --scope project -- python "C:\full\path\to\gns3_mcp\cli.py"

Build .mcpb package:

just build
# Creates: mcp-server\mcp-server.mcpb

Docker Deployment

Run GNS3 MCP Server in Docker for isolated deployment, easier management, and multi-platform support.

Quick Start with Docker Compose

Prerequisites:

• Docker Desktop installed

• GNS3 server running and accessible

• Network access to GNS3 server

Step 1: Download docker-compose.yml

curl -O https://raw.githubusercontent.com/ChistokhinSV/gns3-mcp/master/docker-compose.yml

Step 2: Create .env file

cat > .env <<EOF
GNS3_HOST=192.168.1.20
GNS3_PORT=80
GNS3_USER=admin
GNS3_PASSWORD=your-password
HTTP_PORT=8000
LOG_LEVEL=INFO
EOF

Or copy from template:

curl -O https://raw.githubusercontent.com/ChistokhinSV/gns3-mcp/master/.env.example
mv .env.example .env
# Edit .env with your credentials

Step 3: Start services

# Start MCP server and SSH proxy
docker-compose up -d

# View logs
docker-compose logs -f

# Check health
curl http://localhost:8000/health
curl http://localhost:8022/health

Step 4: Configure Claude Desktop/Code

For Claude Code (HTTP mode):

claude mcp add --transport http gns3-mcp --url http://localhost:8000

For Claude Desktop, add to MCP configuration:

{
  "mcpServers": {
    "gns3-mcp": {
      "transport": {
        "type": "http",
        "url": "http://localhost:8000"
      }
    }
  }
}

Using Docker Run (without compose)

docker run -d \
  --name gns3-mcp-server \
  -p 8000:8000 \
  -e GNS3_HOST=192.168.1.20 \
  -e GNS3_PORT=80 \
  -e GNS3_USER=admin \
  -e GNS3_PASSWORD=your-password \
  --restart unless-stopped \
  chistokhinsv/gns3-mcp:latest

Container Management

# View logs
docker-compose logs -f gns3-mcp
docker-compose logs -f ssh-proxy

# Restart services
docker-compose restart

# Stop services
docker-compose down

# Update to latest version
docker-compose pull
docker-compose up -d

Environment Variables

See .env.example for complete list.

Architecture

The Docker deployment includes two containers:

1. gns3-mcp - Main MCP server (port 8000)

   • Provides MCP protocol access to GNS3

   • HTTP/SSE transport modes

   • Bridge network mode

2. gns3-ssh-proxy - SSH gateway (port 8022)

   • Enables SSH access to lab devices

   • Host network mode (required for isolated lab networks)

   • Netmiko-based automation

Troubleshooting

Container won't start:

docker-compose logs gns3-mcp
docker-compose logs ssh-proxy

Cannot connect to GNS3:

# Test from container
docker exec gns3-mcp-server curl -v http://192.168.1.20/v3/version

# Check connectivity
docker exec gns3-mcp-server ping -c 3 192.168.1.20

Health check failing:

# Manual health check
curl -v http://localhost:8000/health

# Check container status
docker ps --filter name=gns3-mcp

For more details, see docs/DOCKER_HUB.md.

Documentation

• CHANGELOG.md - Version history and release notes

• DEPLOYMENT.md - SSH proxy deployment instructions

• docs/architecture/ - Architecture documentation and C4 diagrams

License

MIT License

Author

Sergei Chistokhin (Sergei@Chistokhin.com)