GNS3 Node Operations

Manage network device nodes in GNS3 projects. Add devices from templates, control power state, and access consoles for configuration and troubleshooting.

When to Use

• Adding network devices (routers, switches, firewalls) to a lab
• Starting or stopping individual nodes
• Reloading nodes after configuration changes
• Suspending nodes to save state
• Starting or stopping all nodes in a project
• Getting console access information for device configuration
• Isolating nodes for testing without deleting links

MCP Server

• Command: python3 -u mcp-servers/gns3-mcp-server/gns3_mcp_server.py (stdio transport)
• Requires: GNS3_URL, GNS3_USER, GNS3_PASSWORD environment variables

Available Tools

| Tool | Parameters | What It Does | |------|------------|--------------| | gns3_list_nodes | project_id | List all nodes in a project with status | | gns3_create_node | project_id, template, name?, x?, y?, compute_id? | Create node from template | | gns3_start_node | project_id, node_id | Start a node (power on) | | gns3_stop_node | project_id, node_id | Stop a node (power off) | | gns3_suspend_node | project_id, node_id | Suspend a node (save state) | | gns3_reload_node | project_id, node_id | Reload a node (restart) | | gns3_bulk_node_action | project_id, action | Apply action to all nodes (start/stop/suspend/reload) | | gns3_get_node_console | project_id, node_id | Get console connection info |

Utility Tools

| Tool | Parameters | What It Does | |------|------------|--------------| | gns3_list_templates | None | List available node templates on the server | | gns3_list_computes | None | List available compute servers |

Workflow Examples

Build a Lab Topology

bash
# List available templates
"List GNS3 templates"

# Add devices to the lab
"Add a Cisco IOSv router to routing-test"
"Add an Arista vEOS switch to routing-test"
"Add a VPCS host to routing-test"

Control Node Power State

bash
# Start individual nodes
"Start router1 in routing-test"

# Start all nodes at once
"Start all nodes in routing-test"

# Stop when done
"Stop all nodes in routing-test"

Console Access

bash
# Get console connection info
"Show console info for router1 in routing-test"
# Returns: telnet 192.168.1.100 5000

Reload After Config Changes

bash
# Reload a router after making changes
"Reload router1 in routing-test"

Template Fuzzy Matching

The gns3_create_node tool supports fuzzy matching for template names:

• "Cisco IOSv" matches "Cisco IOSv 15.9(3)M2"
• "vEOS" matches "Arista vEOS 4.28.0F"
• "VPCS" matches "VPCS" exactly

Integration with Other Skills

• gns3-project-lifecycle: Create a project first
• gns3-link-management: Connect nodes after creation
• gns3-packet-capture: Capture traffic on links between nodes

Error Handling

| Error Code | Meaning | Resolution | |------------|---------|------------| | GNS3_NOT_FOUND | Node or project doesn't exist | Check name/ID | | GNS3_CONFLICT | Node already running/stopped | Check current state first | | GNS3_VALIDATION | Invalid template name | Use gns3_list_templates to find valid names |

Notes

• Nodes can be referenced by name or UUID
• Template matching is case-insensitive
• Bulk actions affect all nodes in the project
• Console info varies by node type (telnet, VNC, HTTP)
• All operations logged to GAIT audit trail