Filebeat sidecar container setup and configuration in OOM

The aggregated logging framework (Logging Architecture), uses Filebeat to send logs from each pod to the ELK stack where they are processed and stored. This requires each pod to have an additional container which will run Filebeat, and for the necessary log files to be accessible between containers.

A reference log demon node project exists that can be used as a guideline for the suggested setup in OOM:

https://gerrit.onap.org/r/gitweb?p=logging-analytics.git;a=tree;f=reference/logging-kubernetes/logdemonode;h=8f84219f008e648d5ade5137dd3f6591863b1af2;hb=d882270162d56c55da339af8fb9384e1bdc0160d

For the setup, we will add two resource files:

1. filebeat.yml. This is the filebeat configuration file which determines the path to find log files and any other configuration of Filebeat
2. logback.xml. This is the specification of the log format and location.

The deployment in OOM is done via Helm.

1. Add filebeat.yml to resources (e.g. oom/kubernetes/<component>/resources/config/log/filebeat/filebeat.yml)

   A sample filebeat.yml can be found in the log demon node project:
   https://gerrit.onap.org/r/gitweb?p=logging-analytics.git;a=tree;f=reference/logging-kubernetes/logdemonode/charts/logdemonode/resources/config/log/filebeat;h=abf4f0a84ae7a15ed99fc4776727e4333948b583;hb=d882270162d56c55da339af8fb9384e1bdc0160d

   
   

2. Add Filebeat container to deployment.yaml:
   
   

           # Filebeat sidecar container
           - name: {{ include "common.name" . }}-filebeat-onap
             image: "{{ .Values.global.loggingRepository }}/{{ .Values.global.loggingImage }}"
             imagePullPolicy: {{ .Values.global.pullPolicy | default .Values.pullPolicy }}
             volumeMounts:
             - name: {{ include "common.fullname" . }}-filebeat-conf
               mountPath: /usr/share/filebeat/filebeat.yml
               subPath: filebeat.yml
             - name: {{ include "common.fullname" . }}-data-filebeat
               mountPath: /usr/share/filebeat/data
             - name: {{ include "common.fullname" . }}-logs
               mountPath: /var/log/onap
   
   

   Here the image and pull policy and based on global values. 
   The {{ include "common.fullname" . }}-filebeat-conf volume mount is used to share the filebeat.yml config resource. 

   The {{ include "common.fullname" . }}-logs volume mount is used to share the application logs for other containers in the pod

   The {{ include "common.fullname" . }}-data-filebeat volume mount is used to share filebeat logs

3. Add configmap to component to reference the filebeat.yml file that will be deployed to container (e.g. kubernetes/<component>/templates/configmap.yaml:

   apiVersion: v1
   kind: ConfigMap
   metadata:
     name: {{ .Release.Name }}-<component>-filebeat-configmap
     namespace: {{ include "common.namespace" . }}
   data:
   {{ tpl (.Files.Glob "resources/config/log/filebeat/filebeat.yml").AsConfig . | indent 2 }}

   Replace <component> with the component name 

4. Add filebeat repo and image specification to values.yaml and config of service name and port:
   In file, oom/kubernetes/<component>/values.yaml, add 

   
   

   global:
     loggingRepository: docker.elastic.co
     loggingImage: beats/filebeat:5.5.0
   
   # application configuration
   config:
     logstashServiceName: log-ls
     logstashPort: 5044

5. Add logback.xml file to microservice resources:
   kubernetes/<component>/charts/<microservice>/resources/config/logback.xml

   A sample logback can be found here:
   https://gerrit.onap.org/r/gitweb?p=logging-analytics.git;a=tree;f=reference/logging-kubernetes/logdemonode/charts/logdemonode/resources/config;hb=d882270162d56c55da339af8fb9384e1bdc0160d

   
   

6. Create configmap for microservice to share logback.xml with application container:

   Create/modify file, oom/kubernetes/pomba/charts/pomba-aaictxbuilder/templates/configmap.yaml

   apiVersion: v1
   kind: ConfigMap
   metadata:
     name: {{ include "common.fullname" . }}-log
     namespace: {{ include "common.namespace" . }}
   data:
   {{ tpl (.Files.Glob "resources/config/logback.xml").AsConfig . | indent 2 }}

   
   

7. Add volume mounts to microservice deployment.yaml to share logs and reference logback.xml:

   Modify container section of file, oom/kubernetes/<component>/charts/<microservice>/templates/deployment.yaml

             volumeMounts:
             - name: {{ include "common.fullname" . }}-logs
               mountPath: /var/log/onap
             - mountPath: /opt/ajsc/etc/config/logback.xml
               name: {{ include "common.fullname" . }}-log-conf
               subPath: logback.xml

   Note volumeMounts section may already exist. If so, just add new content to the existing section

   
   

8. Add volumes specification to microservice deployment.yaml to 1) share logback.xml via configmap, 2) share filebeat.yml via configmap, 3) share filebeat data via emptyDir 4) share application log data via emptyDir
   Add/modify volumes section of file, oom/kubernetes/<component>/charts/<microservice>/templates/deployment.yaml

         volumes:
           - name: {{ include "common.fullname" . }}-log-conf
             configMap:
               name: {{ include "common.fullname" . }}-log
           - name: {{ include "common.fullname" . }}-filebeat-conf
             configMap:
               name: {{ .Release.Name }}-<component>-filebeat-configmap
           - name: {{ include "common.fullname" . }}-data-filebeat
             emptyDir: {}
           - name:  {{ include "common.fullname" . }}-logs
             emptyDir: {}

   Replace <component> with the component name
   If volumes section already exists, add content to existing section