Installing the Agent on Kubernetes

Agent Installation

There are different ways of installing the instana-agent onto a Kubernetes cluster. While having the Agent installed manually directly on the host will do the job of monitoring containers and processes on that host it will not be able to collect Kubernetes data. To have full experience of monitoring Kubernetes cluster with Kubernetes data we recommend to use the below documented ways to deploy the agent through a YAML file or a Helm Chart.

Agent Installation through YAML file

To install and configure Instana within your Kubernetes Cluster as a DaemonSet you simply need to define the DaemonSet YAML file and execute the below command. Below is an example of a YAML file to run the Instana agent. Once the YAML file is customized you can simply start it through kubectl:

kubectl apply -f instana-agent.yaml

Example YAML file

As with all deployments in Kubernetes, it’s a really good idea to make use of namespaces to keep things organized. The following YAML creates a Namespace called instana-agent in which the DaemonSet will be created. This allows you to tag the agents to isolate them or even stop all of them at once by simply deleting the instana-agent namespace.

You need to change the BASE64_ENCODED_INSTANA_KEY in the file below. The variable is a base64 encoded Instana key for the cluster to which the generated data is sent.

To get your Instana Agent key base64 encoded simply run:

echo YOUR_INSTANA_AGENT_KEY | base64

NoteINSTANA_ZONE is used to name and uniquely identify Kubernetes cluster in your environment NoteINSTANA_AGENT_ENDPOINT and INSTANA_AGENT_ENDPOINT_PORT might also need to be adjusted depending on your deployment type (SaaS or On-Premises) and region. Please see Agent Configuration for details.

If you make make changes in ConfigMap for configuration.yaml, instana-agent DaemonSet needs to be recreated. Easiest way to apply the changes is to do following

kubectl delete -f instana-agent.yaml
kubectl apply -f instana-agent.yaml

Below is the example instana-agent.yaml file to run the agent as a DaemonSet in Kubernetes:

Download this file

apiVersion: v1
kind: Namespace
metadata:
  name: instana-agent
---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: instana-agent
  namespace: instana-agent
---
apiVersion: v1
kind: Secret
metadata:
  name: instana-agent-secret
  namespace: instana-agent
type: Opaque
data:
  key: # echo YOUR_INSTANA_AGENT_KEY | base64
---
apiVersion: v1
kind: ConfigMap
metadata:
  name: instana-configuration
  namespace: instana-agent
data:
  configuration.yaml: |
    # Example of configuration yaml template

    # Manual a-priori configuration. Configuration will be only used when the sensor
    # is actually installed by the agent.
    # The commented out example values represent example configuration and are not
    # necessarily defaults. Defaults are usually 'absent' or mentioned separately.
    # Changes are hot reloaded unless otherwise mentioned.

    # It is possible to create files called 'configuration-abc.yaml' which are
    # merged with this file in file system order. So 'configuration-cde.yaml' comes
    # after 'configuration-abc.yaml'. Only nested structures are merged, values are
    # overwritten by subsequent configurations.

    # Secrets
    # To filter sensitive data from collection by the agent, all sensors respect
    # the following secrets configuration. If a key collected by a sensor matches
    # an entry from the list, the value is redacted.
    #com.instana.secrets:
    #  # One of: 'equals-ignore-case', 'equals', 'contains-ignore-case', 'contains', 'regex'
    #  matcher: 'contains-ignore-case'
    #  list:
    #    - 'key'
    #    - 'password'
    #    - 'secret'

    # Host
    #com.instana.plugin.host:
    #  tags:
    #    - 'dev'
    #    - 'app1'

    # Hardware & Zone
    #com.instana.plugin.generic.hardware:
    #  enabled: true # disabled by default
    #  availability-zone: 'zone'
---
apiVersion: extensions/v1beta1
kind: DaemonSet
metadata:
  name: instana-agent
  namespace: instana-agent
spec:
  template:
    metadata:
      labels:
        app: instana-agent
    spec:
      serviceAccount: instana-agent
      hostIPC: true
      hostNetwork: true
      hostPID: true
      containers:
        - name: instana-agent
          image: instana/agent
          imagePullPolicy: Always
          env:
            - name: INSTANA_AGENT_LEADER_ELECTOR_PORT
              value: "42655"
            - name: INSTANA_ZONE
              value: k8s-cluster-name
            - name: INSTANA_AGENT_ENDPOINT
              value: saas-us-west-2.instana.io
            - name: INSTANA_AGENT_ENDPOINT_PORT
              value: "443"
            - name: INSTANA_AGENT_KEY
              valueFrom:
                secretKeyRef:
                  name: instana-agent-secret
                  key: key
            - name: JAVA_OPTS
              # Approximately 1/3 of container memory limits to allow for direct-buffer memory usage and JVM overhead
              value: "-Xmx170M -XX:+ExitOnOutOfMemoryError"
            - name: INSTANA_AGENT_POD_NAME
              valueFrom:
                fieldRef:
                  fieldPath: metadata.name
          securityContext:
            privileged: true
          volumeMounts:
            - name: dev
              mountPath: /dev
            - name: run
              mountPath: /run
            - name: var-run
              mountPath: /var/run
            - name: sys
              mountPath: /sys
            - name: log
              mountPath: /var/log
            - name: machine-id
              mountPath: /etc/machine-id
            - name: configuration
              subPath: configuration.yaml
              mountPath: /root/configuration.yaml
          livenessProbe:
            httpGet: # Agent liveness is published on localhost:42699/status
              path: /status
              port: 42699
            initialDelaySeconds: 75
            periodSeconds: 5
          resources:
            requests:
              memory: "512Mi"
              cpu: "0.5"
            limits:
              memory: "512Mi"
              cpu: "1.5"
          ports:
            - containerPort: 42699
        - name: instana-agent-leader-elector
          image: instana/leader-elector:0.5.1
          env:
            - name: INSTANA_AGENT_POD_NAME
              valueFrom:
                fieldRef:
                  fieldPath: metadata.name
          args: ["--election=instana", "--http=localhost:42655", "--id=$(INSTANA_AGENT_POD_NAME)"]
          resources:
            requests:
              cpu: "0.1"
              memory: "64Mi"
          livenessProbe:
            httpGet: # Leader elector liveness is tied to Agent, published on localhost:42699/status
              path: /status
              port: 42699
            initialDelaySeconds: 75
            periodSeconds: 5
          ports:
            - containerPort: 42655
      volumes:
        - name: dev
          hostPath:
            path: /dev
        - name: run
          hostPath:
            path: /run
        - name: var-run
          hostPath:
            path: /var/run
        - name: sys
          hostPath:
            path: /sys
        - name: log
          hostPath:
            path: /var/log
        - name: machine-id
          hostPath:
            path: /etc/machine-id
        - name: configuration
          configMap:
            name: instana-configuration
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: instana-agent-role
rules:
- nonResourceURLs:
    - "/version"
    - "/healthz"
  verbs: ["get"]
- apiGroups: ["batch"]
  resources:
    - "jobs"
  verbs: ["get", "list", "watch"]
- apiGroups: ["extensions"]
  resources:
    - "deployments"
    - "replicasets"
    - "ingresses"
  verbs: ["get", "list", "watch"]
- apiGroups: ["apps"]
  resources:
    - "deployments"
    - "replicasets"
  verbs: ["get", "list", "watch"]
- apiGroups: [""]
  resources:
    - "namespaces"
    - "events"
    - "services"
    - "endpoints"
    - "nodes"
    - "pods"
    - "replicationcontrollers"
    - "componentstatuses"
    - "resourcequotas"
  verbs: ["get", "list", "watch"]
- apiGroups: [""]
  resources:
    - "endpoints"
  verbs: ["create", "update", "patch"]
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: instana-agent-role-binding
  namespace: instana-agent
subjects:
- kind: ServiceAccount
  name: instana-agent
  namespace: instana-agent
roleRef:
  kind: ClusterRole
  name: instana-agent-role
  apiGroup: rbac.authorization.k8s.io

RBAC

Notes:

  • To be able to deploy for Kubernetes versions prior to 1.8 with RBAC enabled, replace rbac.authorization.k8s.io/v1 with rbac.authorization.k8s.io/v1beta1 for RBAC api version

  • You might need to grant your user the ability to create authorization roles. In GKE for example you can do this with following command:

    kubectl create clusterrolebinding cluster-admin-binding \
    --clusterrole cluster-admin --user $(gcloud config get-value account)

If you don’t have RBAC enabled you will need to remove the ClusterRole and ClusterRoleBinding from the above configuration.

Agent Installation through a Helm Chart

To ease up installation we have written a Helm chart which packages and pre-configures the needed Kubernetes resources. For instructions on how to install it with helm please visit helm/charts/stable/instana-agent

Agent Installation on Google Kubernetes Engine

If you are running on the Google Kubernetes Engine you can install the agent through a Kubernetes Application listed in the Google Cloud Platform Marketplace.

Configuring network access for monitored applications

Some types of applications need to reach out to the agent first. Currently they are

  • Node.js
  • Go
  • Ruby
  • Python

Those applications need to know on which IP the agent is listening. As the agent will listen on the host IP automatically, use the following Downward API snippet to pass it in an environment variable to the application pod:

spec:
  containers:
    env:
      - name: INSTANA_AGENT_HOST
        valueFrom:
          fieldRef:
            fieldPath: status.hostIP