# pfsense_update_system_dns

A write tool on the Pfsense MCP server.

Agent View of the PolicyLayer registry record for `pfsense_update_system_dns`. HTML page: https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-update-system-dns

## Facts

- Tool: `pfsense_update_system_dns`
- Server: Pfsense (`abl030/pfsense-mcp`) — https://policylayer.com/tools/abl030-pfsense-mcp.md
- Homepage: https://github.com/abl030/pfsense-mcp
- Risk category: Write (Medium risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Rate-limited

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "pfsense_update_system_dns",
    "arguments": {}
  }
}
```

## Why pfsense_update_system_dns is rated Medium

The tool name suggests it modifies the system DNS configuration on a pfSense firewall. Changing DNS settings can redirect all DNS resolution for the network, enabling traffic interception or denial of service. Severity is high due to blast radius on network security. Confidence is moderate because the description is empty, so we rely solely on the tool name.

From the tool's own definition: "Tool name: pfsense_update_system_dns — 'update' implies modification; 'system_dns' implies DNS resolver/forwarder configuration on the firewall"

## Use case

AI agents use pfsense_update_system_dns to create or update resources in Pfsense, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Pfsense environment.

## Recommended policy (PolicyLayer)

Verdict: **Rate-limited**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Pfsense:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "pfsense_update_system_dns": {
      "limits": [
        {
          "counter": "pfsense_update_system_dns_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}
```

## Other tools on Pfsense (679)

- `pfsense_delete_auth_key` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-auth-key.md
- `pfsense_delete_auth_keys` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-auth-keys.md
- `pfsense_delete_diagnostics_arp_table` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-diagnostics-arp-table.md
- `pfsense_delete_diagnostics_arp_table_entry` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-diagnostics-arp-table-entry.md
- `pfsense_delete_diagnostics_config_history_revision` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-diagnostics-config-history-revision.md
- `pfsense_delete_diagnostics_config_history_revisions` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-diagnostics-config-history-revisions.md
- `pfsense_delete_diagnostics_table` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-diagnostics-table.md
- `pfsense_delete_firewall_alias` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-alias.md
- `pfsense_delete_firewall_aliases` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-aliases.md
- `pfsense_delete_firewall_nat_one_to_one_mapping` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-nat-one-to-one-mapping.md
- `pfsense_delete_firewall_nat_one_to_one_mappings` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-nat-one-to-one-mappings.md
- `pfsense_delete_firewall_nat_outbound_mapping` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-nat-outbound-mapping.md
- `pfsense_delete_firewall_nat_outbound_mappings` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-nat-outbound-mappings.md
- `pfsense_delete_firewall_nat_port_forward` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-nat-port-forward.md
- `pfsense_delete_firewall_nat_port_forwards` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-nat-port-forwards.md
- `pfsense_delete_firewall_rule` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-rule.md
- `pfsense_delete_firewall_rules` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-rules.md
- `pfsense_delete_firewall_schedule` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-schedule.md
- `pfsense_delete_firewall_schedule_time_range` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-schedule-time-range.md
- `pfsense_delete_firewall_schedule_time_ranges` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-schedule-time-ranges.md
- `pfsense_delete_firewall_schedules` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-schedules.md
- `pfsense_delete_firewall_state` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-state.md
- `pfsense_delete_firewall_states` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-states.md
- `pfsense_delete_firewall_traffic_shaper` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-traffic-shaper.md
- `pfsense_delete_firewall_traffic_shaper_limiter` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-traffic-shaper-limiter.md
- `pfsense_delete_firewall_traffic_shaper_limiter_bandwidth` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-traffic-shaper-limiter-bandwidth.md
- `pfsense_delete_firewall_traffic_shaper_limiter_bandwidths` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-traffic-shaper-limiter-bandwidths.md
- `pfsense_delete_firewall_traffic_shaper_limiter_queue` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-traffic-shaper-limiter-queue.md
- `pfsense_delete_firewall_traffic_shaper_limiter_queues` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-traffic-shaper-limiter-queues.md
- `pfsense_delete_firewall_traffic_shaper_queue` — Destructive — https://policylayer.com/tools/abl030-pfsense-mcp/pfsense-delete-firewall-traffic-shaper-queue.md
- …and 649 more: https://policylayer.com/tools/abl030-pfsense-mcp.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=abl030-pfsense-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/abl030-pfsense-mcp