Elasticsearch integration for logs

1. Integrate Elasticsearch to WebLogic Kubernetes Operator

For reference information, see Elasticsearch integration for the WebLogic Kubernetes Operator.

To enable elasticsearch integration, you must edit file ${WORKDIR}/charts/weblogic-operator/values.yaml before deploying the WebLogic Kubernetes Operator.

# elkIntegrationEnabled specifies whether or not ELK integration is enabled.                                            
elkIntegrationEnabled: true                                                                                             
                                                                                                                        
# logStashImage specifies the docker image containing logstash.                                                         
# This parameter is ignored if 'elkIntegrationEnabled' is false.                                                        
logStashImage: "logstash:6.8.23"                                                                                         
                                                                                                                        
# elasticSearchHost specifies the hostname of where Elasticsearch is running.                                           
# This parameter is ignored if 'elkIntegrationEnabled' is false.                                                        
elasticSearchHost: "elasticsearch.default.svc.cluster.local"                                                            
                                                                                                                        
# elasticSearchPort specifies the port number of where Elasticsearch is running.                                        
# This parameter is ignored if 'elkIntegrationEnabled' is false.                                                        
elasticSearchPort: 9200

After you’ve deployed WebLogic Kubernetes Operator and made the above changes, the weblogic-operator pod will have additional Logstash container. The Logstash container will push the weblogic-operator logs to the configured Elasticsearch server.

2. Publish WebLogic Server and WebCenter Content Logs using Logstash Pod

You can publish the WebLogic Server logs to Elasticsearch Server using Logstash pod. This Logstash pod must have access to the shared domain home. For the WebCenter Content wccinfra, you can use the persistent volume of the domain home in the Logstash pod. The steps to create the Logstash pod are as follows:

Get the persistent volume details of the domain home of the WebLogic Server(s). The following command will list the persistent volume details in the namespace - “wccns”:

$ kubectl get pv -n wccns
NAME                 CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS   CLAIM                       STORAGECLASS                    REASON   AGE
wccinfra-domain-pv   10Gi       RWX            Retain           Bound    wccns/wccinfra-domain-pvc   wccinfra-domain-storage-class            33d

Create the deployment yaml for Logstash pod by updating the logstash.yaml, located at $WORKDIR/logging-services/logstash/logstash.yaml according to your configurations. The mounted persistent volume of the domain home will provide access to the WebLogic server logs to Logstash pod. Given below is a sample Logstash deployment yaml.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: logstash
  namespace: wccns
spec:
  selector:
    matchLabels:
      app: logstash
  template: # create pods using pod definition in this template
    metadata:
      labels:
        app: logstash
    spec:
      volumes:
      - name: weblogic-domain-storage-volume
        persistentVolumeClaim:
          claimName: wccinfra-domain-pvc
      - name: shared-logs
        emptyDir: {}
      containers:
      - name: logstash
        image: logstash:6.8.23
        command: ["/bin/sh"]
        args: ["/usr/share/logstash/bin/logstash", "-f", "/u01/oracle/user_projects/domains/logstash.conf"]
        imagePullPolicy: IfNotPresent
        volumeMounts:
        - mountPath: /u01/oracle/user_projects/domains
          name: weblogic-domain-storage-volume
        - name: shared-logs
          mountPath: /shared-logs
        ports:
        - containerPort: 5044
          name: logstash

Sample Logstash configuration file is located at $WORKDIR/logging-services/logstash/logstash.conf

$ vi $WORKDIR/logging-services/logstash/logstash.conf
input {                                                                                                                
  file {                                                                                                               
    path => "/u01/oracle/user_projects/domains/wccinfra/servers/**/logs/*-diagnostic.log"                                          
    start_position => beginning                                                                                        
  }              
  file {                                                                                                               
    path => "/u01/oracle/user_projects/domains/logs/wccinfra/*.log"                                          
    start_position => beginning                                                                                        
  }                                                                                                                                                                                                                                       
}

filter {                                                                                                               
  grok {                                                                                                               
    match => [ "message", "<%{DATA:log_timestamp}> <%{WORD:log_level}> <%{WORD:thread}> <%{HOSTNAME:hostname}> <%{HOSTNAME:servername}> <%{DATA:timer}> <<%{DATA:kernel}>> <> <%{DATA:uuid}> <%{NUMBER:timestamp}> <%{DATA:misc}> <%{DATA:log_number}> <%{DATA:log_message}>" ]                                                                                        
  }                                                                                                                    
}                                                                                                                         
output {                                                                                                               
  elasticsearch {                                                                                                      
    hosts => ["elasticsearch.default.svc.cluster.local:9200"]                                                          
  }                                                                                                                    
}

This sample configuration will publish all server and Diagnostic logs under wccinfra to Logstash.

$ kubectl cp $WORKDIR/logging-services/logstash/logstash.conf wccns/wccinfra-adminserver:/u01/oracle/user_projects/domains/logstash.conf

Deploy Logstash pod

After you have created the Logstash deployment yaml and Logstash configuration file, deploy Logstash using following command:

$ kubectl create -f $WORKDIR/logging-services/logstash/logstash.yaml

3. Test the deployment of Elasticsearch and Kibana

The WebLogic Kubernetes Operator also provides a sample deployment of Elasticsearch and Kibana for testing purpose. You can deploy Elasticsearch and Kibana on the Kubernetes cluster as shown below:

$ cd ${WORKDIR}/elasticsearch-and-kibana/
$ kubectl create -f elasticsearch_and_kibana.yaml
Get the Kibana dashboard port information as shown below:

Wait for pods to start:

-bash-4.2$ kubectl get pods -w
NAME                            READY   STATUS    RESTARTS   AGE
elasticsearch-8bdb7cf54-mjs6s   1/1     Running   0          4m3s
kibana-dbf8964b6-n8rcj          1/1     Running   0          4m3s
-bash-4.2$ kubectl get svc
NAME            TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)             AGE
elasticsearch   ClusterIP   10.105.205.157   <none>        9200/TCP,9300/TCP   10d
kibana          NodePort    10.98.104.41     <none>        5601:30412/TCP      10d
kubernetes      ClusterIP   10.96.0.1        <none>        443/TCP             42d

You can access the Kibana dashboard at http://<your_hostname>:30412/. In our example, the node port would be 30412.

Create an Index Pattern in Kibana

Create an index pattern logstash-* in Kibana > Management. After the servers are started, you will see the log data in the Kibana dashboard.