hot-reload of pipeline configs without restarting logstash pods

[morganchristiansson]

Describe the feature:

https://www.elastic.co/guide/en/logstash/current/reloading-config.html

Describe a specific use case for the feature:

Starting logstash can be slow. Hot-reloading config files should help when updating logstash pipelines via helm values.

Seems to me it's just a matter of adding --config.reload.automatic and removing/disabling this code in logstash/templates/statefulset.yaml

{{/* This forces a restart if the configmap has changed */}}
{{- if .Values.logstashConfig }}
configchecksum: {{ include (print .Template.BasePath "/configmap-config.yaml") . | sha256sum | trunc 63 }}
{{- end }}
{{/* This forces a restart if the configmap has changed */}}
{{- if .Values.logstashPipeline }}
pipelinechecksum: {{ include (print .Template.BasePath "/configmap-pipeline.yaml") . | sha256sum | trunc 63 }}
{{- end }}

Or is restart preferred for any reason?

[drenze]

Kubernetes won't reload changed configmaps. The only way to force the reload is by including the config checksum, which forces the pod to reload.

[morganchristiansson]

https://kubernetes.io/docs/tasks/configure-pod-container/configure-pod-configmap/#mounted-configmaps-are-updated-automatically

as long as subPath option is not used the configmap values are reloaded into volumes, aswell as environment variables from envFrom: I believe.

[morganchristiansson]

Also need --config.reload.automatic per https://www.elastic.co/guide/en/logstash/current/reloading-config.html

[botelastic]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[botelastic]

This issue has been automatically closed because it has not had recent activity since being marked as stale.

[jmlrt]

This is still relevant

[botelastic]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[jmlrt]

still valid

[botelastic]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[jmlrt]

still valid

[smallersoup]

still valid

[liladler]

Since secrets are automatically reloaded without restarting the pods, what worked for me is to configure Logstash with a stringData Secret while setting config.reload.automatic: true in logstash.yml

[chas0amx]

@liladler
In the Chart we have ConfigMap, not Secret. Is it possible to configure Logstash with Secret?

https://github.com/elastic/helm-charts/blob/master/logstash/templates/configmap-pipeline.yaml

[botelastic]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[jmlrt]

still valid

[botelastic]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[jmlrt]

still valid

[botelastic]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[botelastic]

This issue has been automatically closed because it has not had recent activity since being marked as stale.

[cchriso]

still valid