Container Compute Service:Use an AliyunLogConfig to collect application logs

Prerequisites

Before you begin, ensure that you have an ACS cluster.

Step 1: Install the alibaba-log-controller add-on

When creating an ACS cluster, select the Enable Log Service check box to install alibaba-log-controller automatically. If you skipped this step, install the add-on after cluster creation:

1. Log on to the ACS console. In the left-side navigation pane, click Clusters.

2. On the Clusters page, click the ID of the target cluster. In the left-side navigation pane of the cluster details page, choose Operations > Add-ons.

3. In the Logs and Monitoring section, find alibaba-log-controller and click Install. In the Install alibaba-log-controller dialog box, click OK.

Step 2: Create an AliyunLogConfig CRD to configure log collection

In the left-side navigation pane of the cluster details page, choose Custom Resources > CRDs > Create from YAML to create an AliyunLogConfig.

apiVersion: log.alibabacloud.com/v1alpha1
kind: AliyunLogConfig
metadata:
  name: test-stdout
spec:
  project: k8s-log-c326bc86****    # Replace with the actual project name.
  logstore: test-stdout
  shardCount: 2
  lifeCycle: 90
  logtailConfig:
    inputType: plugin
    configName: test-stdout
    inputDetail:
      plugin:
        inputs:
          - type: service_docker_stdout
            detail:
              Stdout: true
              Stderr: true
              K8sNamespaceRegex: ^(default)$
              K8sContainerRegex: ^(busybox)$
              K8sPodRegex: ^backend.+$
              IncludeK8sLabel:
                app: backend
                application: prod

Scenario 2: Collect text logs from specific applications

To scope collection to specific pods or containers, add Kubernetes filter conditions to the advanced field inside logtailConfig. After deploying the AliyunLogConfig, SLS collects text logs only from pods that match the filters.

apiVersion: log.alibabacloud.com/v1alpha1
kind: AliyunLogConfig
metadata:
  name: test-file
spec:
  project: k8s-log-c326bc86****    # Replace with the actual project name.
  logstore: test-file
  logtailConfig:
    inputType: file
    configName: test-file
    inputDetail:
      logType: common_reg_log
      logPath: /log/
      filePattern: "*.log"
      dockerFile: true
      advanced:
        k8s:
          K8sNamespaceRegex: ^(default)$
          K8sContainerRegex: ^(busybox)$
          K8sPodRegex: ^backend.+$
          IncludeK8sLabel:
            app: backend
            application: prod

Note

After creating the AliyunLogConfig, check the SLS console to confirm the corresponding Logstore is created (see Step 4). If a Logstore is missing, review your Logtail configurations and correct any parameter errors.

Step 3: Create a test application

After deploying the AliyunLogConfig, SLS automatically collects logs from newly created pods that match the filter conditions. Deploy the following Deployment to generate test logs — the container continuously prints both stdout and text log output.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: backend-busybox
  labels:
    app: backend
    application: prod
spec:
  replicas: 1
  selector:
    matchLabels:
      app: backend
      application: prod
  template:
    metadata:
      name: backend-busybox
      labels:
        app: backend
        application: prod
    spec:
      containers:
      - args:
        - -c
        - mkdir -p /log; while true; do echo hello world; date; echo hello sls >> /log/busybox.log; sleep 1; done
        command:
        - /bin/sh
        image: registry-cn-hangzhou.ack.aliyuncs.com/ack-demo/busybox:1.28
        imagePullPolicy: Always
        name: busybox

Step 4: View logs in the SLS console

After the Deployment is running, verify that logs are flowing into SLS:

1. Log on to the Simple Log Service console.

2. In the Projects section, find the project for your ACS cluster (default name: k8s-log-{ACS cluster ID}) and click the project name to open the Logstore tab.

3. In the Logstores list, click the name of the Logstore specified in your log collection configuration.

On the log query page, confirm the following:

• The test-stdout Logstore contains log entries with stdout output (for example, hello world and the current date).

• The test-file Logstore contains log entries from the file log (for example, hello sls).

If either Logstore is missing or empty, the AliyunLogConfig may not have been applied correctly. Review the CRD configuration and check the alibaba-log-controller pod logs for errors.

What's next

• To troubleshoot Logtail log collection errors, see What do I do if errors occur when I use Logtail to collect logs?