Medium Risk

update_vpc_subnet

Update an existing subnet in a VPC

How to control update_vpc_subnet ↓

What update_vpc_subnet does on Linode MCP Server

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

Medium Risk

Why update_vpc_subnet needs a policy

This tool modifies existing VPC subnet configuration, which is a reversible Write operation. However, it carries high severity due to the blast radius: incorrect subnet updates could disrupt network connectivity, isolate resources, or cause service outages across multiple instances depending on that subnet.

From the tool's definition Tool name is 'update_vpc_subnet' and description states 'Update an existing subnet in a VPC' — modifies network configuration in cloud infrastructure.

Documented attack patterns abuse exactly the kind of access update_vpc_subnet gives an agent:

How to control update_vpc_subnet

PolicyLayer is an MCP gateway — it sits between your AI agents and Linode MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for update_vpc_subnet:

policy.json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "update_vpc_subnet": {
      "limits": [
        {
          "counter": "update_vpc_subnet_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

update_vpc_subnet stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

  1. Create a free account and register Linode MCP Server — nothing to install.
  2. Add this policy — paste it, or build it visually.
  3. Point your MCP client (Claude, Cursor, anything) at your gateway URL.
LIMIT THIS TOOL →

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Related tools and policies

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Questions about update_vpc_subnet

What does the update_vpc_subnet tool do? +

Update an existing subnet in a VPC. It is categorised as a Write tool in the Linode MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on update_vpc_subnet? +

Register the Linode MCP Server MCP server in PolicyLayer and add a rule for update_vpc_subnet: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Linode MCP Server. Nothing to install.

What risk level is update_vpc_subnet? +

update_vpc_subnet is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit update_vpc_subnet? +

Yes. Add a rate_limit block to the update_vpc_subnet rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block update_vpc_subnet completely? +

Set action: deny in the PolicyLayer policy for update_vpc_subnet. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides update_vpc_subnet? +

update_vpc_subnet is provided by the Linode MCP Server MCP server (takashito/linode-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Linode MCP Server tool call.

Start from Linode MCP Server, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

Free to start. No card required.

416 Linode MCP Server tools catalogued and risk-classified — across an index of 43,000+ MCP servers.

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