How-To: Set up Fluentd, Elastic search and Kibana in Kubernetes

前期准备

• Kubernetes (> 1.14)
• kubectl
• Helm 3

Install Elastic search and Kibana

1. Create a Kubernetes namespace for monitoring tools

   kubectl create namespace dapr-monitoring
   

2. Add the helm repo for Elastic Search

   helm repo add elastic https://helm.elastic.co
   helm repo update
   

3. Install Elastic Search using Helm

   By default, the chart creates 3 replicas which must be on different nodes. If your cluster has fewer than 3 nodes, specify a smaller number of replicas. For example, this sets the number of replicas to 1:

   helm install elasticsearch elastic/elasticsearch --version 7.17.3 -n dapr-monitoring --set replicas=1
   

   Otherwise:

   helm install elasticsearch elastic/elasticsearch --version 7.17.3 -n dapr-monitoring
   

   If you are using minikube or simply want to disable persistent volumes for development purposes, you can do so by using the following command:

   helm install elasticsearch elastic/elasticsearch --version 7.17.3 -n dapr-monitoring --set persistence.enabled=false,replicas=1
   

4. Install Kibana

   helm install kibana elastic/kibana --version 7.17.3 -n dapr-monitoring
   

5. Ensure that Elastic Search and Kibana are running in your Kubernetes cluster

   $ kubectl get pods -n dapr-monitoring
   NAME                            READY   STATUS    RESTARTS   AGE
   elasticsearch-master-0          1/1     Running   0          6m58s
   kibana-kibana-95bc54b89-zqdrk   1/1     Running   0          4m21s
   

Install Fluentd

1. Install config map and Fluentd as a daemonset

   Download these config files:

   • fluentd-config-map.yaml

   • fluentd-dapr-with-rbac.yaml

   Note: If you already have Fluentd running in your cluster, please enable the nested json parser so that it can parse JSON-formatted logs from Dapr.

   Apply the configurations to your cluster:

   kubectl apply -f ./fluentd-config-map.yaml
   kubectl apply -f ./fluentd-dapr-with-rbac.yaml
   

2. Ensure that Fluentd is running as a daemonset. The number of FluentD instances should be the same as the number of cluster nodes. In the example below, there is only one node in the cluster:

   $ kubectl get pods -n kube-system -w
   NAME                          READY   STATUS    RESTARTS   AGE
   coredns-6955765f44-cxjxk      1/1     Running   0          4m41s
   coredns-6955765f44-jlskv      1/1     Running   0          4m41s
   etcd-m01                      1/1     Running   0          4m48s
   fluentd-sdrld                 1/1     Running   0          14s
   

Install Dapr with JSON formatted logs

1. Install Dapr with enabling JSON-formatted logs

   helm repo add dapr https://dapr.github.io/helm-charts/
   helm repo update
   helm install dapr dapr/dapr --namespace dapr-system --set global.logAsJson=true
   

2. Enable JSON formatted log in Dapr sidecar

   Add the dapr.io/log-as-json: "true" annotation to your deployment yaml. 例如：

   apiVersion: apps/v1
   kind: Deployment
   metadata:
     name: pythonapp
     namespace: default
     labels:
       app: python
   spec:
     replicas: 1
     selector:
       matchLabels:
         app: python
     template:
       metadata:
         labels:
           app: python
         annotations:
           dapr.io/enabled: "true"
           dapr.io/app-id: "pythonapp"
           dapr.io/log-as-json: "true"
   ...
   

Search logs

Note: Elastic Search takes a time to index the logs that Fluentd sends.

1. Port-forward from localhost to svc/kibana-kibana

   $ kubectl port-forward svc/kibana-kibana 5601 -n dapr-monitoring
   Forwarding from 127.0.0.1:5601 -> 5601
   Forwarding from [::1]:5601 -> 5601
   Handling connection for 5601
   Handling connection for 5601
   

2. Browse to http://localhost:5601

3. Expand the drop-down menu and click Management → Stack Management

   

4. On the Stack Management page, select Data → Index Management and wait until dapr-* is indexed.

   

5. Once dapr-* is indexed, click on Kibana → Index Patterns and then the Create index pattern button.

   

6. Define a new index pattern by typing dapr* into the Index Pattern name field, then click the Next step button to continue.

   

7. Configure the primary time field to use with the new index pattern by selecting the @timestamp option from the Time field drop-down. Click the Create index pattern button to complete creation of the index pattern.

   

8. The newly created index pattern should be shown. Confirm that the fields of interest such as scope, type, app_id, level, etc. are being indexed by using the search box in the Fields tab.

   Note: If you cannot find the indexed field, please wait. The time it takes to search across all indexed fields depends on the volume of data and size of the resource that the elastic search is running on.

   

9. To explore the indexed data, expand the drop-down menu and click Analytics → Discover.

   

10. In the search box, type in a query string such as scope:* and click the Refresh button to view the results.

    Note: This can take a long time. The time it takes to return all results depends on the volume of data and size of the resource that the elastic search is running on.

    

References

• Fluentd for Kubernetes
• Elastic search helm chart
• Kibana helm chart
• Kibana Query Language
• Troubleshooting using Logs