Container Service for Kubernetes:Collect application logs by using pod environment variables

Log on to the ACK console. In the left navigation pane, click Clusters.

On the Clusters page, click the name of the cluster you want to manage. In the left navigation pane, choose Workloads > Deployments.

Select a namespace from the Namespace drop-down list, then click Create from Image in the upper-right corner.

In the Basic Information step, set Name, Replicas, and Type. Click Next.

In the Container step, configure the Log Service section. The following figure shows an example configuration.

Click Next to configure advanced settings. For remaining steps, see Create a Deployment.

Log on to the ACK console. In the left navigation pane, click Clusters.

On the Clusters page, click the name of the cluster you want to manage. In the left navigation pane, choose Workloads > Deployments.

Select a namespace from the Namespace drop-down list, then click Create from YAML in the upper-right corner.

Select a template from the Sample Template drop-down list, edit the template in the Template code editor, then click Create. The following example pod YAML collects stdout to the log-stdout Logstore and log files from /var/log/*.log to the log-varlog Logstore:

• Set the value to stdout to collect stdout and stderr.

• Set the value to a file path (for example, /var/log/*.log) to collect log files.

apiVersion: v1
kind: Pod
metadata:
  name: my-demo
spec:
  containers:
  - name: my-demo-app
    image: 'registry.cn-hangzhou.aliyuncs.com/log-service/docker-log-test:latest'
    args:
    - -c
    - mkdir -p /log;while true; do echo hello world; date; echo hello sls >> /var/log/test.log; sleep 1;done
    command:
    - /bin/sh
    env:
    # Log collection: collect stdout to the log-stdout Logstore
    - name: aliyun_logs_log-stdout
      value: stdout
    # Log collection: collect /var/log/*.log files to the log-varlog Logstore
    - name: aliyun_logs_log-varlog
      value: /var/log/*.log
    # Custom tag: append tag1=v1 to all collected logs
    - name: aliyun_logs_mytag1_tags
      value: tag1=v1
    volumeMounts:
    - name: volumn-sls-mydemo
      mountPath: /var/log
  volumes:
  - name: volumn-sls-mydemo
    emptyDir: {}

All environment variables for log collection must use the aliyun_logs_ prefix. Log collection variables use the format aliyun_logs_{key}, where {key} becomes both the Logstore name and the collection configuration name. The {key} can contain only lowercase letters, digits, and hyphens (-), and must be unique across the cluster. Custom tag variables use the format aliyun_logs_{key}_tags with a {tag-key}={tag-value} value. The tag is automatically appended to all logs collected from the pod. Volume configuration: When collecting log files (not stdout), configure volumeMounts so that LoongCollector can access the log directory. In the example above, mountPath: /var/log gives LoongCollector access to /var/log/*.log.