# Drop

> Drop unwanted telemetry at ingestion layer using Control Plane

Source: https://last9.io/docs/control-plane-drop/

![Control Plane — Pipeline Sequence: Drop](../../../../../assets/content/docs/control-plane/ingestion/control-plane-pipeline-sequence-drop.jpg)

<figcaption class="-mt-6">Order of Last9's pipeline processing.</figcaption>

[Drop](https://app.last9.io/control-plane/drop) lets you discard unwanted telemetry that you don't want to store and query, at runtime — no code changes, no redeploys, no policy updates. For example, if you need debug logs during an incident, just remove the drop rule. It's a faster, simpler alternative to code-level governance.

:::caution[Data Loss Warning]
Dropped data is **not ingested** and **cannot be recovered**. Always use the preview button to verify your filters match the intended data before saving.
:::

## Create a Drop Rule

Head to the [Control Plane](https://app.last9.io/control-plane/drop) and click **NEW RULE**.

![Control Plane — New Drop Rule](../../../../../assets/content/docs/control-plane/ingestion/drop/control-plane-drop-rule-new.png)

### Step 1: Select Telemetry Type

Choose the type of telemetry you want to drop:

| Telemetry   | Filter By                               |
| ----------- | --------------------------------------- |
| **Metrics** | Metric name only                        |
| **Logs**    | Attributes and resource attributes      |
| **Traces**  | Span attributes and resource attributes |

### Step 2: Define Filters

Add one or more filter conditions. Multiple filters are combined using **AND** logic — all conditions must match for data to be dropped.

![Control Plane — Drop Rule](../../../../../assets/content/docs/control-plane/ingestion/drop/control-plane-drop-rule.png)

#### Filter Operators

| Operator   | Symbol | Description                                |
| ---------- | ------ | ------------------------------------------ |
| Equals     | `==`   | Exact match                                |
| Not Equals | `!=`   | Does not match                             |
| Regex      | `=~`   | Pattern matching using regular expressions |

#### Filter Keys (Logs & Traces)

For logs and traces, filter keys use the OpenTelemetry attribute format:

- `attributes["key"]` — Span or log attributes (e.g., `attributes["http.status_code"]`)
- `resource.attributes["key"]` — Resource-level attributes (e.g., `resource.attributes["service.name"]`)

### Step 3: Preview & Verify

Before saving, use the preview button to verify matching data. The button label changes based on telemetry type:

- **Metrics**: Click **VIEW IN DASHBOARD** → Opens Grafana with matching metric query
- **Logs**: Click **VIEW LOGS** → Opens Logs Explorer with matching filters
- **Traces**: Click **VIEW TRACES** → Opens Traces Explorer with matching filters

### Step 4: Name & Save

Give your rule a unique name and click **SAVE**. Rule names must be unique within your organization.

:::note
Drop rules take **1-2 minutes** to take effect after saving.
:::

## Examples

### Drop debug logs from development environment

| Field     | Value                                                              |
| --------- | ------------------------------------------------------------------ |
| Telemetry | Logs                                                               |
| Filter 1  | `resource.attributes["deployment.environment"]` `==` `development` |
| Filter 2  | `attributes["level"]` `==` `debug`                                 |

### Drop health check traces

| Field     | Value                                         |
| --------- | --------------------------------------------- |
| Telemetry | Traces                                        |
| Filter    | `attributes["http.route"]` `=~` `.*/health.*` |

### Drop specific metric

| Field     | Value                              |
| --------- | ---------------------------------- |
| Telemetry | Metrics                            |
| Filter    | Name `==` `go_gc_duration_seconds` |

## Manage Existing Rules

All your drop rules are displayed in a table below the create form. To manage a rule:

1. Click the **three-dot menu** (⋮) on the rule row
2. Select an action:
   - **Edit**: Opens the rule in the form for modification
   - **Delete**: Removes the rule (requires confirmation)

:::note
Deleting a drop rule resumes ingestion of previously dropped data. Changes take **1-2 minutes** to take effect.
:::

## Constraints

- **Unique names**: Each drop rule must have a unique name
- **AND logic only**: Multiple filters are combined with AND (all must match)
- **Ingestion limits**: Your organization may have limits on the total number of ingestion rules
- **Regex validation**: When using the `=~` operator, the value must be a valid regular expression

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## Troubleshooting

Please get in touch with us on [Discord](https://discord.com/invite/Q3p2EEucx9) or [Email](mailto:support@last9.io) if you have any questions.