namedrop are not honored

[jryberg]

Relevant telegraf.conf

[[inputs.docker]]
  namedrop = ["docker_container_cpu_container_id"]
  endpoint = "unix:///var/run/docker.sock"
  perdevice = false
  perdevice_include = ["cpu"]

Logs from Telegraf

2025-04-23T08:34:29Z E! [serializers.prometheusremotewrite::http] some series were dropped, 1280 series left to send; last recorded error: failed to parse "docker_container_cpu_container_id": bad sample value "d6a4fd0573cfd669aea5dda3ff15eb8069440e2b9a3c8f9b3e071b41c4d491fb"
2025-04-23T08:34:29Z E! [serializers.prometheusremotewrite::http] some series were dropped, 1280 series left to send; last recorded error: failed to parse "docker_container_cpu_container_id": bad sample value "d6a4fd0573cfd669aea5dda3ff15eb8069440e2b9a3c8f9b3e071b41c4d491fb"
2025-04-23T08:35:29Z E! [serializers.prometheusremotewrite::http] some series were dropped, 1378 series left to send; last recorded error: failed to parse "docker_container_cpu_container_id": bad sample value "34c106efcbc121cf551b108202a3d6dbca68ffabfa1a5724ccbf5869faa19427"
2025-04-23T08:35:29Z E! [serializers.prometheusremotewrite::http] some series were dropped, 1378 series left to send; last recorded error: failed to parse "docker_container_cpu_container_id": bad sample value "34c106efcbc121cf551b108202a3d6dbca68ffabfa1a5724ccbf5869faa19427"
2025-04-23T08:36:29Z E! [serializers.prometheusremotewrite::http] some series were dropped, 1378 series left to send; last recorded error: failed to parse "docker_container_cpu_container_id": bad sample value "573d548b231f4713bb68df543cc365375be76f33ed1dd683564e6c889763001b"
2025-04-23T08:36:29Z E! [serializers.prometheusremotewrite::http] some series were dropped, 1378 series left to send; last recorded error: failed to parse "docker_container_cpu_container_id": bad sample value "573d548b231f4713bb68df543cc365375be76f33ed1dd683564e6c889763001b"
2025-04-23T08:37:29Z E! [serializers.prometheusremotewrite::http] some series were dropped, 1378 series left to send; last recorded error: failed to parse "docker_container_cpu_container_id": bad sample value "df50386f5bd614dec7dd85e1843181d5876a6f320344d3f96b2b9641f2e8212c"
2025-04-23T08:37:29Z E! [serializers.prometheusremotewrite::http] some series were dropped, 1378 series left to send; last recorded error: failed to parse "docker_container_cpu_container_id": bad sample value "df50386f5bd614dec7dd85e1843181d5876a6f320344d3f96b2b9641f2e8212c"
2025-04-23T08:38:29Z E! [serializers.prometheusremotewrite::http] some series were dropped, 1378 series left to send; last recorded error: failed to parse "docker_container_cpu_container_id": bad sample value "a4148c7a257041d75c185eb4594e3cf249df0c9106275bf93d53a2a5f446aad2"
2025-04-23T08:38:29Z E! [serializers.prometheusremotewrite::http] some series were dropped, 1378 series left to send; last recorded error: failed to parse "docker_container_cpu_container_id": bad sample value "a4148c7a257041d75c185eb4594e3cf249df0c9106275bf93d53a2a5f446aad2"
2025-04-23T08:39:29Z E! [serializers.prometheusremotewrite::http] some series were dropped, 1378 series left to send; last recorded error: failed to parse "docker_container_cpu_container_id": bad sample value "d6a4fd0573cfd669aea5dda3ff15eb8069440e2b9a3c8f9b3e071b41c4d491fb"
2025-04-23T08:39:29Z E! [serializers.prometheusremotewrite::http] some series were dropped, 1378 series left to send; last recorded error: failed to parse "docker_container_cpu_container_id": bad sample value "d6a4fd0573cfd669aea5dda3ff15eb8069440e2b9a3c8f9b3e071b41c4d491fb"

System info

Docker 28.1.1, OS: Debian Bookworm, Telegraf 1.34.2 (git: HEAD@552f7e20)

Docker

No response

Steps to reproduce

Run any output.http with prometheusremotewrite enabled and try to drop metrics that are invalid

Expected behavior

Dropped metrics from the input should not be available for any outputs

Actual behavior

Dropped metrics are still processed by the outputs

Additional info

No response

[Hipska]

Please verify with --test, but docker_container_cpu_container_id is not the name of a metric. (docker_container_cpu is and container_id is a field of that metric)

[jryberg]

@Hipska , Sorry. I was just using what the log output told me was the metric name. I guess some logs are including fields as a compound name of sorts for the resulting metrics for the output.

I will try to change my filters

[srebhan]

@jryberg is this a real issue or can we close the issue? If so, can you please provide the "raw", unfiltered (and redacted) metrics for me to reproduce the issue?

[jryberg]

@srebhan , you can probably close it.

It was just hard to know the difference between the metric name and the field value since both might contain one or more underscore

I think it's not a bug, but the message is also not helpful.

It would be nice it the message was something like:

2025-04-23T08:36:29Z E! [serializers.prometheusremotewrite::http] some series were dropped, 1378 series left to send; last recorded error: failed to parse "docker_container_cpu", field "container_id": bad sample value "573d548b231f4713bb68df543cc365375be76f33ed1dd683564e6c889763001b"

But I have since then learned how do deal with it. It's just about user experience

[srebhan]

Thanks for reporting back @jryberg!