I am using Fluentd as a sidecar to ship nginx logs to stdout so they show up in the Pod's logs. I have a strange problem that Fluentd is not picking up the configuration when the container starts.

Upon examining the Fluentd startup logs it appears that the configuration is not being loaded. The config is supposed to be loaded from /etc/fluentd-config/fluentd.conf when the container starts. I have connected to the container and the config file is correct, and the pv mounts are also correct. The environment variable also exists.

The full deployment spec is below - and is self contained if you feel like playing with it.

apiVersion: v1
kind: List
items:
- apiVersion: v1
  kind: PersistentVolume
  metadata:
    name: weblog-pv
    labels:
      type: local
  spec:
    storageClassName: manual
    accessModes: 
    - ReadWriteOnce
    hostPath:
      path: /tmp/weblog
      type: DirectoryOrCreate
    capacity: 
      storage: 500Mi

- apiVersion: v1
  kind: PersistentVolumeClaim
  metadata:
    name: weblog-pvc
  spec:
    storageClassName: manual
    accessModes:
    - ReadWriteOnce
    resources:
      requests:
        storage: 200Mi

- apiVersion: v1
  kind: ConfigMap
  metadata:
    name: fluentd-config
  data:
    fluentd.conf: |
      <source>
        @type tail
        format none
        path /var/log/nginx/access.log
        tag count.format1
      </source>
      <match *.**>
        @type forward
        <server>
          name localhost
          host 127.0.0.1
        </server>
      </match>

- apiVersion: v1
  kind: Pod
  metadata:
    name: sidecar-example
    labels:
      app: webserver
  spec:
    containers:
    - name: nginx
      image: nginx:latest
      ports: 
      - containerPort: 80
      volumeMounts:
      - name: logging-vol
        mountPath: /var/log/nginx
    - name: fdlogger
      env:
        - name: FLUENTD_ARGS
          value: -c /etc/fluentd-config/fluentd.conf
      image: fluent/fluentd
      volumeMounts:
      - name: logging-vol
        mountPath: /var/log/nginx
      - name: log-config
        mountPath: /etc/fluentd-config
    volumes:
      - name: logging-vol
        persistentVolumeClaim: 
          claimName: weblog-pvc
      - name: log-config
        configMap:
          name: fluentd-config

- apiVersion: v1
  kind: Service
  metadata:
    name: sidecar-svc
  spec:
    selector:
      app:  webserver
    type: NodePort
    ports:
    - name:  sidecar-port
      port:  80
      nodePort:  32000