docs-v2/content/kapacitor/v1.6/event_handlers/snmptrap.md

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---
title: SNMP trap event handler
list_title: SNMP trap
description: >
The "snmptrap" event handler allows you to send Kapacitor alerts SNMP traps. This page includes configuration options and usage examples.
menu:
kapacitor_1_6_ref:
name: SNMP Trap
weight: 1700
parent: Event handlers
---
The SNMP trap event handler sends alert messages as SNMP traps.
## Configuration
Configuration as well as default [option](#options) values for the SNMP trap
event handler are set in your `kapacitor.conf`.
Below is an example configuration:
```toml
[snmptrap]
enabled = true
addr = "localhost:162"
community = "kapacitor"
retries = 1
```
#### `enabled`
Set to `true` to enable the SNMP trap event handler.
#### `addr`
The `host:port` address of the SNMP trap server.
#### `community`
The community to use for traps.
#### `retries`
Number of retries when sending traps.
## Options
The following SNMP trap event handler options can be set in a
[handler file](/kapacitor/v1.6/event_handlers/#create-a-topic-handler-with-a-handler-file) or when using
`.snmpTrap()` in a TICKscript.
| Name | Type | Description |
| ---- | ---- | ----------- |
| trap-oid | string | OID of the trap. |
| data-list | object | Each data object has `oid`, `type`, and `value` fields. Each field is a string. |
### SNMP Trap Data Types
The SNMP trap event handler supports the following data types:
| Abbreviation | Datatype |
| ------------ | -------- |
| c | Counter |
| i | Integer |
| n | Null |
| s | String |
| t | Time ticks |
### Example: handler file
```yaml
id: handler-id
topic: topic-name
kind: snmptrap
options:
trap-oid: 1.3.6.1.4.1.1
data-list:
- oid: 1.3.6.1.4.1.1.5
type: s
value: '{{ .Level }}'
- oid: 1.3.6.1.4.1.1.6
type: i
value: 50
- oid: 1.3.6.1.4.1.1.7
type: c
value: '{{ index .Fields "num_requests" }}'
- oid: 1.3.6.1.4.1.1.8
type: s
value: '{{ .Message }}'
```
### Example: TICKscript
```js
|alert()
// ...
.snmpTrap('1.3.6.1.4.1.1')
.data('1.3.6.1.4.1.1.5', 's', '{{ .Level }}')
.data('1.3.6.1.4.1.1.6', 'i', '50')
.data('1.3.6.1.4.1.1.7', 'c', '{{ index .Fields "num_requests" }}')
.data('1.3.6.1.4.1.1.8', 's', '{{ .Message }}')
```
## Using the SNMP trap event handler
The SNMP trap event handler can be used in both TICKscripts and handler files
to send alerts as SNMP traps.
### Sending SNMP traps from a TICKscript
The following TICKscript uses the `.snmptrap()` event handler to send alerts as
SNMP traps whenever idle CPU usage drops below 10%.
_**snmptrap-cpu-alert.tick**_
```js
stream
|from()
.measurement('cpu')
|alert()
.crit(lambda: "usage_idle" < 10)
.message('Hey, check your CPU')
.snmpTrap('1.3.6.1.2.1.1')
.data('1.3.6.1.2.1.1.7', 'i', '{{ index .Field "value" }}')
```
### Publish to multiple topics from a defined handler
The following setup sends an alert to the `cpu` topic with the message,
"Hey, check your CPU".
An SNMP trap handler is added that subscribes to the `cpu` topic and sends new
alerts as SNMP traps.
Create a TICKscript that publishes alert messages to a topic.
The TICKscript below sends an alert message to the `cpu` topic any time idle CPU
usage drops below 10%.
_**cpu\_alert.tick**_
```js
stream
|from()
.measurement('cpu')
|alert()
.crit(lambda: "usage_idle" < 10)
.message('Hey, check your CPU')
.topic('cpu')
```
Add and enable the TICKscript:
```bash
kapacitor define cpu_alert -tick cpu_alert.tick
kapacitor enable cpu_alert
```
Create a handler file that subscribes to the `cpu` topic and uses the SNMP trap
event handler to send alerts as SNMP traps.
_**snmptrap\_cpu\_handler.yaml**_
```yaml
id: snmptrap-cpu-alert
topic: cpu
kind: snmptrap
options:
trap-oid: '1.3.6.1.2.1.1'
data-list:
- oid: '1.3.6.1.2.1.1.7'
type: i
value: '{{ index .Field "value" }}'
```
Add the handler:
```bash
kapacitor define-topic-handler snmptrap_cpu_handler.yaml
```