# This configuration file for Fluentd / td-agent is used # to watch changes to Docker log files. The kubelet creates symlinks that # capture the pod name, namespace, container name & Docker container ID # to the docker logs for pods in the /var/log/containers directory on the host. # If running this fluentd configuration in a Docker container, the /var/log # directory should be mounted in the container. # # These logs are then submitted to Elasticsearch which assumes the # installation of the fluent-plugin-elasticsearch & the # fluent-plugin-kubernetes_metadata_filter plugins. # See https://github.com/uken/fluent-plugin-elasticsearch & # https://github.com/fabric8io/fluent-plugin-kubernetes_metadata_filter for # more information about the plugins. # Maintainer: Jimmi Dyson # # Example # ======= # A line in the Docker log file might look like this JSON: # # {"log":"2014/09/25 21:15:03 Got request with path wombat\n", # "stream":"stderr", # "time":"2014-09-25T21:15:03.499185026Z"} # # The time_format specification below makes sure we properly # parse the time format produced by Docker. This will be # submitted to Elasticsearch and should appear like: # $ curl 'http://elasticsearch-logging:9200/_search?pretty' # ... # { # "_index" : "logstash-2014.09.25", # "_type" : "fluentd", # "_id" : "VBrbor2QTuGpsQyTCdfzqA", # "_score" : 1.0, # "_source":{"log":"2014/09/25 22:45:50 Got request with path wombat\n", # "stream":"stderr","tag":"docker.container.all", # "@timestamp":"2014-09-25T22:45:50+00:00"} # }, # ... # # The Kubernetes fluentd plugin is used to write the Kubernetes metadata to the log # record & add labels to the log record if properly configured. This enables users # to filter & search logs on any metadata. # For example a Docker container's logs might be in the directory: # # /var/lib/docker/containers/997599971ee6366d4a5920d25b79286ad45ff37a74494f262e3bc98d909d0a7b # # and in the file: # # 997599971ee6366d4a5920d25b79286ad45ff37a74494f262e3bc98d909d0a7b-json.log # # where 997599971ee6... is the Docker ID of the running container. # The Kubernetes kubelet makes a symbolic link to this file on the host machine # in the /var/log/containers directory which includes the pod name and the Kubernetes # container name: # # synthetic-logger-0.25lps-pod_default_synth-lgr-997599971ee6366d4a5920d25b79286ad45ff37a74494f262e3bc98d909d0a7b.log # -> # /var/lib/docker/containers/997599971ee6366d4a5920d25b79286ad45ff37a74494f262e3bc98d909d0a7b/997599971ee6366d4a5920d25b79286ad45ff37a74494f262e3bc98d909d0a7b-json.log # # The /var/log directory on the host is mapped to the /var/log directory in the container # running this instance of Fluentd and we end up collecting the file: # # /var/log/containers/synthetic-logger-0.25lps-pod_default_synth-lgr-997599971ee6366d4a5920d25b79286ad45ff37a74494f262e3bc98d909d0a7b.log # # This results in the tag: # # var.log.containers.synthetic-logger-0.25lps-pod_default_synth-lgr-997599971ee6366d4a5920d25b79286ad45ff37a74494f262e3bc98d909d0a7b.log # # The Kubernetes fluentd plugin is used to extract the namespace, pod name & container name # which are added to the log message as a kubernetes field object & the Docker container ID # is also added under the docker field object. # The final tag is: # # kubernetes.var.log.containers.synthetic-logger-0.25lps-pod_default_synth-lgr-997599971ee6366d4a5920d25b79286ad45ff37a74494f262e3bc98d909d0a7b.log # # And the final log record look like: # # { # "log":"2014/09/25 21:15:03 Got request with path wombat\n", # "stream":"stderr", # "time":"2014-09-25T21:15:03.499185026Z", # "kubernetes": { # "namespace": "default", # "pod_name": "synthetic-logger-0.25lps-pod", # "container_name": "synth-lgr" # }, # "docker": { # "container_id": "997599971ee6366d4a5920d25b79286ad45ff37a74494f262e3bc98d909d0a7b" # } # } # # This makes it easier for users to search for logs by pod name or by # the name of the Kubernetes container regardless of how many times the # Kubernetes pod has been restarted (resulting in a several Docker container IDs). # # TODO: Propagate the labels associated with a container along with its logs # so users can query logs using labels as well as or instead of the pod name # and container name. This is simply done via configuration of the Kubernetes # fluentd plugin but requires secrets to be enabled in the fluent pod. This is a # problem yet to be solved as secrets are not usable in static pods which the fluentd # pod must be until a per-node controller is available in Kubernetes. # Prevent fluentd from handling records containing its own logs. Otherwise # it can lead to an infinite loop, when error in sending one message generates # another message which also fails to be sent and so on. type null # Example: # {"log":"[info:2016-02-16T16:04:05.930-08:00] Some log text here\n","stream":"stdout","time":"2016-02-17T00:04:05.931087621Z"} type tail path /var/log/containers/*.log pos_file /var/log/es-containers.log.pos time_format %Y-%m-%dT%H:%M:%S.%NZ tag kubernetes.* format json read_from_head true # Example: # 2015-12-21 23:17:22,066 [salt.state ][INFO ] Completed state [net.ipv4.ip_forward] at time 23:17:22.066081 type tail format /^(?