Introduction

In Kubernetes, checking logs is essential for debugging and monitoring your application. Logs provide valuable insights into how pods are running and can help identify issues in your containerized applications.

Why Check Pod Logs?

• 🔍 **Debugging** – Helps you troubleshoot issues in your applications.
• 📊 **Monitoring** – Gives you visibility into the health and performance of your pods.
• 📅 **Audit** – Logs can be used for auditing the behavior and actions of containers.

Basic Command to Check Logs

To view logs from a specific pod, use the following command:

kubectl logs 

Replace `` with the name of your pod. If the pod has multiple containers, you'll need to specify the container name as well:

kubectl logs  -c 

Example

Let's say you have a pod called nginx-pod running an Nginx web server. To view its logs:

kubectl logs nginx-pod

If there are multiple containers in the pod, you can specify the container name like this:

kubectl logs nginx-pod -c nginx-container

Viewing Logs for Previous Instances of a Pod

Sometimes, a pod may crash and Kubernetes will automatically restart it. To view the logs of the previous instance of the pod, use the --previous flag:

kubectl logs  --previous

This is especially useful when debugging issues caused by a pod crash or failure.

Fetching Logs for All Pods in a Namespace

If you want to view logs for all pods in a specific namespace, you can use the following command:

kubectl logs -n  --selector=

For example, to view logs of all pods with the label app=nginx in the default namespace:

kubectl logs -n default --selector=app=nginx

Tail Logs

You can view the latest logs from your pod by following them with the --follow option. This will show real-time logs as they are generated:

kubectl logs  --follow

Use Ctrl + C to stop following the logs.

Using Log Aggregation Tools

In a production environment, it's common to use log aggregation tools to manage logs from multiple pods. Some popular tools for log aggregation include:

• 📊 **Elasticsearch, Fluentd, and Kibana (EFK) Stack**
• 📦 **Prometheus & Grafana for metrics**
• 💻 **Loki & Grafana for log aggregation**

These tools help aggregate logs from multiple pods and provide advanced querying and visualization capabilities.

Conclusion

Viewing pod logs in Kubernetes is a powerful way to monitor and troubleshoot your applications. Whether you're working with one pod or managing a large number of them, using the kubectl logs command will help you keep your applications running smoothly.

In the next section, we will explore Kubernetes **Health Checks** and how to ensure your pods are always healthy and responsive.