====== Telegraf ======


===== Problems =====

==== Insufficient lockable memory ====

If you updated your containered Telegraf instance lately, you may get a warning to increase the lockable memory limit.   

<code ->
2024-08-02T17:08:46Z W! Insufficient lockable memory 64kb when 348kb is required. Please increase the limit for Telegraf in your Operating System!
</code>
<code ->
2024-08-02T17:08:46Z W! Insufficient lockable memory 64kb when 84kb is required. Please increase the limit for Telegraf in your Operating System!
</code>
<code ->
2024-08-02T17:08:46Z W! Insufficient lockable memory 64kb when 228kb is required. Please increase the limit for Telegraf in your Operating System!
</code>

:!: This solution doesn't apply to Kubernetes installations because [[https://github.com/kubernetes/kubernetes/issues/3595|ulimit support is missing]].

If you work with a docker compose file, edit your service accordingly. The ''memlock'' ulimit has to be set to at least the required size in bytes.

<code yaml docker-compose.yml>
services:
  telegraf:
    image: telegraf:1.31-alpine
    restart: on-failure
    volumes:
      - ./conf/telegraf.conf:/etc/telegraf/telegraf.conf
    env:
      - "INFLUX_TOKEN=d2lraS5kZWZlY3QuY2ggaXMgYXdlc29tZQ=="
    ulimits:
      memlock: 524288
</code>

The same configuration for a ''docker run'' command.
<code bash shell>
docker run --restart on-failure -v ./conf/telegraf.conf:/etc/telegraf/telegraf.conf:ro --env INFLUX_TOKEN=d2lraS5kZWZlY3QuY2ggaXMgYXdlc29tZQ== --ulimit memlock=524288 telegraf:1.31-alpine
</code>

How to select the correct value? Multiply the required kb size with 1024.

FIXME :!: this could be wrong information. According to the [[https://linux.die.net/man/5/limits.conf|limits.conf(5)]] man page the expected value is in KB units. => I have to test this. Maybe my limits are set too high at the moment.

^Required^Calculation^memlock^
|84kb|84*1024|86016|
|228kb|228*1024|233472|
|348kb|348*1024|356352|
|512kb|512*1024|524288|