How to get ${kubernetes.namespace_name} for index_name in fluentd?

Question

Did anyone manage to get kubernetes.namespace_name as indexName? I tried this and its not working.

index_name ${kubernetes.namespace_name}.%Y%m%d
         


        

Answer 1

Well, mine here I did by label, I had to add a label on the objects (deployment, statefulset and etc ...) called fluentd: "true"

Example:

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: kafka
  namespace: your-name-space
  labels:
    app: kafka
    version: "2.6.0"
    component: queues
    part-of: appsbots
    managed-by: kubectl
    fluentd: "true"

In the fluent.conf file, I made a configmap for the fluentd Daemonset as shown below.

apiVersion: v1
kind: ConfigMap
metadata:
  name: fluentd-config
  namespace: kube-system
  labels:
    k8s-app: fluentd-logging
    version: v1
    kubernetes.io/cluster-service: "true"
data:
  fluent.conf: |-
    
        # this tells fluentd to not output its log on stdout
        @type null
    

    # here we read the logs from Docker's containers and parse them
    
      @type tail
      path /var/log/containers/*.log
      pos_file /var/log/containers.log.pos
      tag kubernetes.*
      read_from_head true
      
        @type json
        time_format %Y-%m-%dT%H:%M:%S.%NZ
      
      
        format /^(?.+) (?stdout) [^ ]* (?.*)$/
        time_format %Y-%m-%dT%H:%M:%S.%N%:z
      
    

    # Kubernetes metadata
    
        @type kubernetes_metadata
    

    
      @type null
    

    # 
    # @type null
    # 

    
      @type null
    
    

    
      @type grep
      
        key $["kubernetes"]["labels"]["fluentd"]        
        pattern true
      
    


    
      @type grep
      
        key $["kubernetes"]["labels"]["fluentd"]        
        pattern false
      
    
    


    #Just an example of what kind of variables can come inside. This part does not apply as config. Do your config with ENV vars
    
      @type elasticsearch
      @id out_es
      @log_level info
      include_tag_key true
      host "#{ENV['FLUENT_ELASTICSEARCH_HOST']}"
      port "#{ENV['FLUENT_ELASTICSEARCH_PORT']}"
      scheme "#{ENV['FLUENT_ELASTICSEARCH_SCHEME'] || 'http'}"
      ssl_verify "#{ENV['FLUENT_ELASTICSEARCH_SSL_VERIFY'] || 'true'}"
      user "#{ENV['FLUENT_ELASTICSEARCH_USER']}"
      password "#{ENV['FLUENT_ELASTICSEARCH_PASSWORD']}"
      reload_connections "#{ENV['FLUENT_ELASTICSEARCH_RELOAD_CONNECTIONS'] || 'true'}"
      logstash_prefix "#{ENV['FLUENT_ELASTICSEARCH_LOGSTASH_PREFIX'] || 'logstash'}"
      logstash_format true
      buffer_chunk_limit "#{ENV['FLUENT_ELASTICSEARCH_BUFFER_CHUNK_LIMIT_SIZE'] || '2M'}"
      buffer_queue_limit "#{ENV['FLUENT_ELASTICSEARCH_BUFFER_QUEUE_LIMIT_LENGTH'] || '32'}"
      flush_interval "#{ENV['FLUENT_ELASTICSEARCH_BUFFER_FLUSH_INTERVAL'] || '5s'}"
      max_retry_wait "#{ENV['FLUENT_ELASTICSEARCH_BUFFER_RETRY_MAX_INTERVAL'] || '30'}"
      disable_retry_limit num_threads "#{ENV['FLUENT_ELASTICSEARCH_BUFFER_FLUSH_THREAD_COUNT'] || '8'}"
      
           @type file
           path /var/log/fluentd-buffers/kubernetes.system.buffer
           flush_mode interval
           retry_type exponential_backoff
           flush_thread_count 2
           flush_interval 5s
           retry_forever true
           retry_max_interval 30
           chunk_limit_size 2M
           queue_limit_length 32
           overflow_action block
       
    

And now the fluentd Deamon file. The image I am using is reference to version v1.10. however it can be the same saw.

apiVersion: apps/v1
kind: DaemonSet
metadata:
  name: fluentd
  namespace: kube-system
  labels:
    k8s-app: fluentd-logging
    version: v1
    kubernetes.io/cluster-service: "true"
  annotations:
    configmap.reloader.stakater.com/reload: "fluentd-config"
spec:
  selector:
    matchLabels:
      k8s-app: fluentd-logging
  template:
    metadata:
      labels:
        k8s-app: fluentd-logging
        version: v1
        kubernetes.io/cluster-service: "true"
    spec:
      serviceAccount: fluentd
      serviceAccountName: fluentd
      tolerations:
      - key: node-role.kubernetes.io/master
        effect: NoSchedule
      containers:
      - name: fluentd
        image: didevlab/mutpoc:fluentd #base--> fluent/fluentd-kubernetes-daemonset:v1.10-debian-elasticsearch7-1
        imagePullPolicy: Always
        env:
          - name:  FLUENT_ELASTICSEARCH_HOST
            value: "elasticsearch-svc.{{ name_corp }}-{{ app_enviroment }}"
          - name:  FLUENT_ELASTICSEARCH_PORT
            value: "9200"
          - name: FLUENT_ELASTICSEARCH_SCHEME
            value: "http"
          - name: FLUENT_UID
            value: "0"
        resources:
          limits:
            memory: 200Mi
          requests:
            cpu: 100m
            memory: 200Mi
        volumeMounts:        
        - name: varlog
          mountPath: /var/log
        - name: varlibdockercontainers
          mountPath: /var/lib/docker/containers
          readOnly: true
        - name: config-fluentd
          mountPath: /fluentd/etc
      terminationGracePeriodSeconds: 30
      volumes:      
      - name: varlog
        hostPath:
          path: /var/log
      - name: varlibdockercontainers
        hostPath:
          path: /var/lib/docker/containers
      - name: config-fluentd
        configMap:
          name: fluentd-config

\o/Good is that, by boyBR