asdf-kubectl VS fluent-bit

# install kubectl plugin for asdf asdf plugin-add kubectl \ https://github.com/asdf-community/asdf-kubectl.git asdf install kubectl latest # fetch latest kubectl asdf install kubectl latest asdf global kubectl latest # test results of latest kubectl kubectl version --short --client 2> /dev/null

❯ asdf plugin-list --urls --refs act https://github.com/grimoh/asdf-act.git master 8729029 aws-vault https://github.com/beardix/asdf-aws-vault.git master 937a1db awscli https://github.com/MetricMike/asdf-awscli.git main b9ba4c7 docker-slim https://github.com/everpeace/asdf-docker-slim.git master 4ee75a3 golang https://github.com/kennyp/asdf-golang.git master 1f388f1 helm https://github.com/Antiarchitect/asdf-helm.git master 87eef5a java https://github.com/halcyon/asdf-java.git master f0c702f jq https://github.com/ryodocx/asdf-jq.git master 3144577 kubectl https://github.com/asdf-community/asdf-kubectl.git master da7bb0b minikube https://github.com/alvarobp/asdf-minikube.git master 8ca7b8d mysql https://github.com/iroddis/asdf-mysql.git master 3aaf756 nodejs https://github.com/asdf-vm/asdf-nodejs.git master cb61e3d perl https://github.com/ouest/asdf-perl.git master 31bb799 php https://github.com/asdf-community/asdf-php.git master 759843b postgres https://github.com/smashedtoatoms/asdf-postgres.git master 4f8b356 python https://github.com/danhper/asdf-python.git master 8ab052f redis https://github.com/smashedtoatoms/asdf-redis.git master bf1276e ruby https://github.com/asdf-vm/asdf-ruby.git master f134c2d sbt https://github.com/bram2000/asdf-sbt.git master 33f9637 scala https://github.com/asdf-community/asdf-scala.git master 1206055 skaffold https://github.com/virtualstaticvoid/asdf-skaffold.git master c942ecf spark https://github.com/joshuaballoch/asdf-spark.git master 6fe49de

CMD> asdf plugin list all Output sample: [...] kubebuilder https://github.com/virtualstaticvoid/asdf-kubebuilder.git kube-capacity https://github.com/looztra/asdf-kube-capacity.git kubectl *https://github.com/Banno/asdf-kubectl.git kubectl-bindrole https://github.com/looztra/asdf-kubectl-bindrole.git kubectx *https://gitlab.com/wt0f/asdf-kubectx.git kubefedctl https://github.com/kvokka/asdf-kubefedctl.git kubeseal https://github.com/stefansedich/asdf-kubeseal.git kubesec https://github.com/vitalis/asdf-kubesec.git kubespy https://github.com/jfreeland/asdf-kubespy.git kubeval https://github.com/stefansedich/asdf-kubeval.git terraform *https://github.com/Banno/asdf-hashicorp.git terraform-docs *https://github.com/looztra/asdf-terraform-docs.git terraform-lsp https://github.com/bartlomiejdanek/terraform-lsp.git terraform-validator https://github.com/looztra/asdf-terraform-validator.git terragrunt https://github.com/lotia/asdf-terragrunt.git [...]

Fluentbit

$ docker run --rm fluent-bit-dummy WARNING: The requested image's platform (linux/amd64) does not match the detected host platform (linux/arm64/v8) and no specific platform was requested Fluent Bit v1.9.10 * Copyright (C) 2015-2022 The Fluent Bit Authors * Fluent Bit is a CNCF sub-project under the umbrella of Fluentd * https://fluentbit.io [2023/12/24 16:06:59] [ info] [fluent bit] version=1.9.10, commit=557c8336e7, pid=1 [2023/12/24 16:06:59] [ info] [storage] version=1.4.0, type=memory-only, sync=normal, checksum=disabled, max_chunks_up=128 [2023/12/24 16:06:59] [ info] [cmetrics] version=0.3.7 [2023/12/24 16:06:59] [ info] [output:stdout:stdout.0] worker #0 started [2023/12/24 16:06:59] [ info] [sp] stream processor started [0] dummy.0: [1703434019.553880465, {"message"=>"custom dummy"}] [0] dummy.0: [1703434020.555768799, {"message"=>"custom dummy"}] [0] dummy.0: [1703434021.550525174, {"message"=>"custom dummy"}] [0] dummy.0: [1703434022.551563050, {"message"=>"custom dummy"}] [0] dummy.0: [1703434023.551944509, {"message"=>"custom dummy"}] [0] dummy.0: [1703434024.550027843, {"message"=>"custom dummy"}] [0] dummy.0: [1703434025.550901801, {"message"=>"custom dummy"}] [0] dummy.0: [1703434026.549279385, {"message"=>"custom dummy"}] ^C[2023/12/24 16:07:08] [engine] caught signal (SIGINT) [0] dummy.0: [1703434027.549678344, {"message"=>"custom dummy"}] [2023/12/24 16:07:08] [ warn] [engine] service will shutdown in max 5 seconds [2023/12/24 16:07:08] [ info] [engine] service has stopped (0 pending tasks) [2023/12/24 16:07:08] [ info] [output:stdout:stdout.0] thread worker #0 stopping... [2023/12/24 16:07:08] [ info] [output:stdout:stdout.0] thread worker #0 stopped

> Libc is a lot more tricky about signals, since not all libc functions can be safely called from handlers.

And this is a huge thing. People do all kinds of operations in signal handlers completely oblivious to the pitfalls. Pitfalls which often do not manifest, making it a great "it works for me" territory.

I once raised a ticket on fluentbit[1] about it but they have abused signal handlers so thoroughly that I do not think they can mitigate the issue without a major rewriting of the signal and crash handling.

[1] https://github.com/fluent/fluent-bit/issues/4836

Fluentbit is Fluentd's lightweight alternative to itself.

https://fluentbit.io

From here, we can explore other developments and tutorials on Kubernetes, such as o11y or observability (PLG, ELK, ELF, TICK, Jaeger, Pyroscope), service mesh (Linkerd, Istio, NSM, Consul Connect, Cillium), and progressive delivery (ArgoCD, FluxCD, Spinnaker).

From this (https://github.com/fluent/fluent-bit/issues/723), I can see there is no grok support for fluent-bit.

apiVersion: v1 kind: ConfigMap metadata: name: fluent-bit-config namespace: newrelic labels: k8s-app: newrelic-logging data: # Configuration files: server, input, filters and output # ====================================================== fluent-bit.conf: | [SERVICE] Flush 1 Log_Level ${LOG_LEVEL} Daemon off Parsers_File parsers.conf HTTP_Server On HTTP_Listen 0.0.0.0 HTTP_Port 2020 @INCLUDE input-kubernetes.conf @INCLUDE output-newrelic.conf @INCLUDE filter-kubernetes.conf input-kubernetes.conf: | [INPUT] Name tail Tag kube.* Path ${PATH} Parser ${LOG_PARSER} DB /var/log/flb_kube.db Mem_Buf_Limit 7MB Skip_Long_Lines On Refresh_Interval 10 filter-kubernetes.conf: | [FILTER] Name multiline Match * multiline.parser multiline-regex [FILTER] Name record_modifier Match * Record cluster_name ${CLUSTER_NAME} [FILTER] Name kubernetes Match kube.* Kube_URL https://kubernetes.default.svc.cluster.local:443 Merge_Log Off output-newrelic.conf: | [OUTPUT] Name newrelic Match * licenseKey ${LICENSE_KEY} endpoint ${ENDPOINT} parsers.conf: | # Relevant parsers retrieved from: https://github.com/fluent/fluent-bit/blob/master/conf/parsers.conf [PARSER] Name docker Format json Time_Key time Time_Format %Y-%m-%dT%H:%M:%S.%L Time_Keep On [PARSER] Name cri Format regex Regex ^(?[^ ]+) (?stdout|stderr) (?[^ ]*) (?.*)$ Time_Key time Time_Format %Y-%m-%dT%H:%M:%S.%L%z [MULTILINE_PARSER] name multiline-regex key_content message type regex flush_timeout 1000 # # Regex rules for multiline parsing # --------------------------------- # # configuration hints: # # - first state always has the name: start_state # - every field in the rule must be inside double quotes # # rules | state name | regex pattern | next state # ------|---------------|--------------------------------|----------- rule "start_state" "/(Dec \d+ \d+\:\d+\:\d+)(.*)/" "cont" rule "cont" "/^\s+at.*/" "cont"

There are also log forwarding tools like promtail and fluentbit that can be used to both ship logs to something like Loki and produce metrics.

FluentBit, is a logging processor that can help you to push all of your application logs to a central location like an ElasticSearch or OpenSearch cluster.