netdev-ssh-mcp

MCP server for interacting with network devices (switches, routers, firewalls) over SSH.
Supports Arista EOS, Cisco NX-OS, Cisco IOS/IOS-XE, Juniper JunOS, and FortiGate FortiOS.
Exposes network device operations as tools for use with Claude Code / Claude Desktop / Codex
(and other MCP clients)

Tools

get_config

Retrieves the running or startup configuration from an Arista, Cisco Nexus,
Cisco Catalyst, Juniper JunOS, or FortiGate FortiOS device. Sensitive values (passwords, secrets, SNMP community
names, BGP/OSPF/TACACS/RADIUS/IKE keys) are automatically replaced with
deterministic SHA-256 hashes:

enable secret [h:a3f4b2c1d5e6]
snmp-server community [h:f9e1d2b4c3a7] ro
username admin privilege 15 secret [h:a3f4b2c1d5e6]

The same secret value always produces the same hash, so configs from different
devices can be safely compared and diffed — identical hashes mean identical
secrets.

| Parameter | Type | Required | Default | Description |
| --- | --- | --- | --- | --- |
| host | string | yes | — | Hostname or IP address of the device |
| username | string | no | DEVICE_USERNAME | SSH username |
| port | int | no | 22 | SSH port |
| config_type | string | no | running | running or startup; startup is not supported on JunOS or FortiOS |
| device_type | string | no | — | eos, ios, nxos, junos, or fortios |

FortiOS notes:

- Use device_type=fortios to retrieve config with show full-configuration.
- fortigate is accepted as an alias for fortios.
- FortiOS does not support config_type=startup.

run_show_command

Runs operational read commands on a network device and returns the output.
For Arista/Cisco/JunOS, the command must start with show. For FortiOS, the
command must start with get. Append | json for structured output where
supported, or | no-more to disable pagination for text output.

| Parameter | Type | Required | Default | Description |
| --- | --- | --- | --- | --- |
| host | string | yes | — | Hostname or IP address of the device |
| command | string | yes | — | The operational read command to run |
| username | string | no | DEVICE_USERNAME | SSH username |
| port | int | no | 22 | SSH port |
| device_type | string | no | — | eos, ios, nxos, junos, or fortios |

Example commands:

show bgp summary | json
show interfaces status | json
show lldp neighbors detail | json
show inventory | json
show version | json
show ip route | json
get system status
get router info routing-table all

> show running-config and show startup-config are not allowed here — use
> the get_config tool instead.
>
> On FortiOS, show, config, execute, and diagnose commands are blocked
> here. Use get_config, run_ping, or run_traceroute instead.

run_ping

Runs a ping command on network device and returns the output.
Useful for verifying reachability from the device's
perspective — for example, testing connectivity to a BGP peer, next-hop, or
management target.

Use device_type to select the correct command syntax for the target platform.
If omitted, EOS/IOS syntax is used (repeat, size keywords). On FortiOS,
the tool uses execute ping-options ..., runs execute ping, then resets the
options within the same SSH session.

| Parameter | Type | Required | Default | Description |
| --- | --- | --- | --- | --- |
| host | string | yes | — | Hostname or IP address of the device |
| destination | string | yes | — | IP address or hostname to ping |
| username | string | no | DEVICE_USERNAME | SSH username |
| port | int | no | 22 | SSH port |
| count | int | no | — | Number of echo requests to send |
| timeout | int | no | — | Per-probe timeout in seconds; supported on FortiOS |
| source | string | no | — | Source IP address or interface name |
| vrf | string | no | — | VRF name |
| size | int | no | — | Packet size in bytes |
| outgoing_interface | string | no | — | Outgoing interface; supported on FortiOS |
| device_type | string | no | — | eos, ios, nxos, junos, or fortios — controls ping syntax |

FortiOS limitations:

- vrf is not supported in this tool for FortiOS 7.4+.
- | json is not supported for FortiOS operational output.

run_traceroute

Shows the hop-by-hop path from the device to a destination and per-hop latency.
Useful for locating where connectivity breaks, verifying traffic follows the
expected path, and identifying which hop introduces latency.

Use device_type to ensure correct syntax. On IOS, vrf must precede the
destination in the command — specifying device_type=ios handles this
automatically. On FortiOS, the tool uses execute traceroute-options ...,
runs execute traceroute, then resets the options within the same SSH session.

| Parameter | Type | Required | Default | Description |
| --- | --- | --- | --- | --- |
| host | string | yes | — | Hostname or IP address of the device |
| destination | string | yes | — | IP address or hostname to trace to |
| username | string | no | DEVICE_USERNAME | SSH username |
| port | int | no | 22 | SSH port |
| max_hops | int | no | — | Maximum number of hops (TTL) |
| timeout | int | no | — | Per-probe timeout in seconds |
| probe | int | no | — | Number of probes per hop |
| source | string | no | — | Source IP address or interface name |
| vrf | string | no | — | VRF name |
| outgoing_interface | string | no | — | Outgoing interface; supported on FortiOS |
| device_type | string | no | — | eos, ios, nxos, junos, or fortios — controls traceroute syntax |

FortiOS limitations:

- vrf, max_hops, and timeout are not supported in this tool for FortiOS 7.4+.
- | json is not supported for FortiOS operational output.

trust_host_key

Fetches the SSH host key currently presented by a device and optionally adds it
to the configured known_hosts file. Use it in two steps:

1. Call with confirm=false to inspect the current fingerprint.
2. After verifying that fingerprint out of band, call again with
confirm=true to write it to known_hosts.

If a device host key has legitimately changed, call with
replace_existing=true after verifying the new fingerprint.

| Parameter | Type | Required | Default | Description |
| --- | --- | --- | --- | --- |
| host | string | yes | — | Hostname or IP address of the device |
| port | int | no | 22 | SSH port |
| confirm | bool | no | false | When false, only inspect the current key; when true, write it |
| replace_existing | bool | no | false | Replace an existing mismatched key after verification |

Default username

Set DEVICE_USERNAME to avoid specifying username in every tool call:

export DEVICE_USERNAME=admin

The username tool parameter takes precedence if provided.

Authentication

Authentication methods are tried in order:

1. SSH agent — if SSH_AUTH_SOCK is set, the agent is used automatically.
No configuration needed.
2. Password — set via the DEVICE_PASSWORD environment variable (see below).

At least one method must be available at call time.

> Claude Desktop note: Claude Desktop is a GUI application and does not
> inherit your shell environment, so SSH_AUTH_SOCK is not available to the
> MCP server process. Set it explicitly in the env block of the config (see
> the Claude Desktop section below). Claude Code runs in the terminal and
> inherits your shell environment, so no extra configuration is needed there.

Password via environment variable

Set DEVICE_PASSWORD before starting the server:

export DEVICE_PASSWORD=mysecret
netdev-ssh-mcp

The password is never passed through tool parameters or the MCP protocol — it
is read once from the environment at call time and applies to all connections
made by the server process.

Host Key Verification

SSH host key verification is enabled by default. The server uses the current
user's OpenSSH known_hosts file:

- macOS and Linux: ~/.ssh/known_hosts
- Windows: %USERPROFILE%\\.ssh\\known_hosts

You can override the path with either:

- command-line flag: --known-hosts /path/to/known_hosts
- environment variable: SSH_KNOWN_HOSTS

If a device is not present in known_hosts, tool calls fail with a clear error
that includes the presented fingerprint and suggests using trust_host_key.

To disable host key verification entirely, use either:

- command-line flag: --insecure-skip-host-key-check
- environment variable: SKIP_HOST_KEY_CHECK=true

Disabling verification is insecure and should only be used as a temporary
escape hatch.

Installation

macOS (Homebrew)

brew install --cask krisiasty/tap/netdev-ssh-mcp

The binary is installed to $(brew --prefix)/bin/netdev-ssh-mcp. The prefix
depends on the Mac architecture:

| Architecture | Path |
| --- | --- |
| Apple Silicon (M1/M2/M3/M4) | /opt/homebrew/bin/netdev-ssh-mcp |
| Intel | /usr/local/bin/netdev-ssh-mcp |

Run brew --prefix to confirm which applies to your machine.

Build from source

Requires Go 1.26 or later.

go build -o netdev-ssh-mcp .

To install the binary to /usr/local/bin after building (macOS and Linux):

sudo install -m 0755 netdev-ssh-mcp /usr/local/bin/

Integration

In the examples below, replace <path-to-binary> with the full path to the
binary. If installed via Homebrew, run brew --prefix to determine the correct
path (/opt/homebrew on Apple Silicon, /usr/local on Intel), then append
/bin/netdev-ssh-mcp.

Claude Code

Add a project-local .mcp.json at the root of your repository:

{
  "mcpServers": {
    "netdev-ssh-mcp": {
      "command": "<path-to-binary>"
    }
  }
}

With a default username:

{
  "mcpServers": {
    "netdev-ssh-mcp": {
      "command": "<path-to-binary>",
      "env": {
        "DEVICE_USERNAME": "admin"
      }
    }
  }
}

Claude Code runs in the terminal and inherits your shell environment, so
SSH_AUTH_SOCK is available automatically — no extra configuration needed for
SSH agent authentication.

Alternatively, using password authentication:

{
  "mcpServers": {
    "netdev-ssh-mcp": {
      "command": "<path-to-binary>",
      "env": {
        "DEVICE_USERNAME": "admin",
        "DEVICE_PASSWORD": "mysecret"
      }
    }
  }
}

Alternatively, register the server globally with the Claude Code CLI:

claude mcp add netdev-ssh-mcp <path-to-binary>

Claude Desktop

Edit ~/Library/Application Support/Claude/claude_desktop_config.json (macOS)
or %APPDATA%\Claude\claude_desktop_config.json (Windows):

{
  "mcpServers": {
    "netdev-ssh-mcp": {
      "command": "<path-to-binary>"
    }
  }
}

Claude Desktop does not inherit your shell environment, so SSH_AUTH_SOCK
must be set explicitly. Get the current socket path from your terminal:

echo $SSH_AUTH_SOCK

Then add it to the config:

{
  "mcpServers": {
    "netdev-ssh-mcp": {
      "command": "<path-to-binary>",
      "env": {
        "DEVICE_USERNAME": "admin",
        "SSH_AUTH_SOCK": "/private/tmp/com.apple.launchd.XXXXX/Listeners"
      }
    }
  }
}

Note that the socket path changes on every reboot and must be updated in the
config accordingly.

Alternatively, using password authentication:

{
  "mcpServers": {
    "netdev-ssh-mcp": {
      "command": "<path-to-binary>",
      "env": {
        "DEVICE_USERNAME": "admin",
        "DEVICE_PASSWORD": "mysecret"
      }
    }
  }
}

Restart Claude Desktop after editing the config.

Example prompts

- Show me the running config of 10.0.0.1
- Compare the running configs of n9k-1 and n9k-2 and summarize the differences
- Check BGP neighbor status on arista1 and tell me if any sessions are down
- Get the interface status from 10.0.0.1 and list any interfaces that are down
- Review the running config of 10.0.0.1 and flag any security concerns
- Get the LLDP neighbors from 10.0.0.1 and draw a topology diagram
- How is traffic to 192.168.100.0/24 forwarded on 10.0.0.1?
- Check NTP consistency across 10.0.0.1, 10.0.0.2, and 10.0.0.3
- Discover spine-1 neighbors via LLDP/CDP and check EVPN fabric configuration
- Tell me what exact commands to use to fix configuration issues you detected
- Verify if all previously spotted issues are fixed now
- Ping 10.0.0.2 from 10.0.0.1 and tell me if it's reachable
- Check if arista1 can reach all its BGP peers by pinging each one
- Ping 8.8.8.8 from the management VRF on n9k-1
- Traceroute from arista1 to 10.0.0.2 and show me the path
- Run a traceroute from spine-1 to each of its BGP peers and identify any asymmetric paths

Obfuscation

Sensitive values are obfuscated by default in get_config and
run_show_command output. The run_ping tool is not affected — ping output
contains no sensitive values. To disable obfuscation, pass --no-obfuscate:

netdev-ssh-mcp --no-obfuscate

In an MCP config file, pass it via args:

{
  "mcpServers": {
    "netdev-ssh-mcp": {
      "command": "<path-to-binary>",
      "args": ["--no-obfuscate"]
    }
  }
}

Logging

The server logs to stderr (never stdout, which is reserved for the MCP
protocol). The log level is controlled by the LOG_LEVEL environment
variable:

| Value | Description |
| --- | --- |
| debug | Connection details, command strings, byte counts |
| info | Default — tool calls, connect/disconnect, success/failure |
| warn | Warnings only |
| error | Errors only |

LOG_LEVEL=debug netdev-ssh-mcp

Author

Krzysztof Ciepłucha

Disclaimer

This tool was designed and built with the assistance of AI tools. The design
decisions, architecture, and all code have been reviewed and verified by a
human. The project goes through automated security checks, vulnerability
scanning, and static code analysis on every commit.

That said, this software is provided as-is with no guarantees. It may contain
bugs. Use at your own risk.

License

Licensed under the Apache License, Version 2.0. See LICENSE for details.