Run Filebeat on Kubernetes
editRun Filebeat on Kubernetes
editYou can use Filebeat Docker images on Kubernetes to retrieve and ship container logs.
Running Elastic Cloud on Kubernetes? See Run Beats on ECK.
Kubernetes deploy manifests
editYou deploy Filebeat as a DaemonSet to ensure there’s a running instance on each node of the cluster.
The Docker logs host folder (/var/lib/docker/containers
) is mounted on the
Filebeat container. Filebeat starts an input for the files and
begins harvesting them as soon as they appear in the folder.
Everything is deployed under the kube-system
namespace by default. To change
the namespace, modify the manifest file.
To download the manifest file, run:
curl -L -O https://raw.githubusercontent.com/elastic/beats/7.12/deploy/kubernetes/filebeat-kubernetes.yaml
If you are using Kubernetes 1.7 or earlier: Filebeat uses a hostPath volume to persist internal data. It’s located
under /var/lib/filebeat-data
. The manifest uses folder autocreation (DirectoryOrCreate
), which was introduced in
Kubernetes 1.8. You need to remove type: DirectoryOrCreate
from the manifest and create the host folder yourself.
Settings
editBy default, Filebeat sends events to an existing Elasticsearch deployment, if present. To specify a different destination, change the following parameters in the manifest file:
- name: ELASTICSEARCH_HOST value: elasticsearch - name: ELASTICSEARCH_PORT value: "9200" - name: ELASTICSEARCH_USERNAME value: elastic - name: ELASTICSEARCH_PASSWORD value: changeme
Red Hat OpenShift configuration
editIf you are using Red Hat OpenShift, you need to specify additional settings in the manifest file and enable the container to run as privileged.
-
Modify the
DaemonSet
container spec in the manifest file:securityContext: runAsUser: 0 privileged: true
-
Grant the
filebeat
service account access to the privileged SCC:oc adm policy add-scc-to-user privileged system:serviceaccount:kube-system:filebeat
This command enables the container to be privileged as an administrator for OpenShift.
-
Override the default node selector for the
kube-system
namespace (or your custom namespace) to allow for scheduling on any node:oc patch namespace kube-system -p \ '{"metadata": {"annotations": {"openshift.io/node-selector": ""}}}'
This command sets the node selector for the project to an empty string. If you don’t run this command, the default node selector will skip master nodes.
Load Kibana dashboards
editFilebeat comes packaged with various pre-built Kibana dashboards that you can use to visualize logs from your Kubernetes environment.
If these dashboards are not already loaded into Kibana, you must install Filebeat
on any system that can connect to the Elastic Stack, and then run the setup
command to load the dashboards.
To learn how, see Load Kibana dashboards.
The setup
command does not load the ingest pipelines used to parse log lines. By default, ingest pipelines
are set up automatically the first time you run Filebeat and connect to Elasticsearch.
If you are using a different output other than Elasticsearch, such as Logstash, you need to:
Deploy
editTo deploy Filebeat to Kubernetes, run:
kubectl create -f filebeat-kubernetes.yaml
To check the status, run:
$ kubectl --namespace=kube-system get ds/filebeat NAME DESIRED CURRENT READY UP-TO-DATE AVAILABLE NODE-SELECTOR AGE filebeat 32 32 0 32 0 <none> 1m
Log events should start flowing to Elasticsearch. The events are annotated with metadata added by the add_kubernetes_metadata processor.
Parsing json logs
editIt is common case when collecting logs from workloads running on Kubernetes that these applications are logging in json format. In these case, special handling can be applied so as to parse these json logs properly and decode them into fields. Bellow there are provided 2 different ways of configuring filebeat’s autodiscover so as to identify and parse json logs. We will use an example of one Pod with 2 containers where only one of these logs in json format.
Example log:
{"type":"log","@timestamp":"2020-11-16T14:30:13+00:00","tags":["warning","plugins","licensing"],"pid":7,"message":"License information could not be obtained from Elasticsearch due to Error: No Living connections error"}
-
Using
json.*
options with templatesfilebeat.autodiscover: providers: - type: kubernetes node: ${NODE_NAME} templates: - condition: contains: kubernetes.container.name: "no-json-logging" config: - type: container paths: - "/var/log/containers/*-${data.kubernetes.container.id}.log" - condition: contains: kubernetes.container.name: "json-logging" config: - type: container paths: - "/var/log/containers/*-${data.kubernetes.container.id}.log" json.keys_under_root: true json.add_error_key: true json.message_key: message
-
Using
json.*
options with hintsKey part here is to properly annotate the Pod to only parse logs of the correct container as json logs. In this, annotation should be constructed like this:
co.elastic.logs.<container_name>/json.keys_under_root: "true"
Autodiscovery configuration:
filebeat.autodiscover: providers: - type: kubernetes node: ${NODE_NAME} hints.enabled: true hints.default_config: type: container paths: - /var/log/containers/*${data.kubernetes.container.id}.log
Then annotate the pod properly:
annotations: co.elastic.logs.json-logging/json.keys_under_root: "true" co.elastic.logs.json-logging/json.add_error_key: "true" co.elastic.logs.json-logging/json.message_key: "message"
Logrotation
editAccording to kubernetes documentation Kubernetes is not responsible for rotating logs, but rather a deployment tool should set up a solution to address that. Different logrotation strategies can cause issues that might make Filebeat losing events or even duplicating events. Users can find more information about Filebeat’s logrotation best practises at Filebeat’s log rotation specific documentation