Posted onJan 3, 2023 • Edited onDec 30, 2023

Streaming logs of all pods at once

#api #discuss

If you're like me who likes to see all of the log events in a single terminal then you're at right place. In this article we see how to view logs of single container pod with multiple replicas, logs of a particular container of a multi containers pod and logs of all containers of a multi containers pod. Here are the list of commands:

1. Stream logs of single container pod with multiple replicas

In Kubernetes it's all about labels and selectors. And I'm going to demonstrate commands using labels. In case you are not familiar with how to get label details from a pod or how to add label on a pod then jump to the end of this post.

Note: I prefer using alias, here 'k' is alias for kubectl. set it asalias k=kubectl

k logs -f -l <pod-label-value> --prefix

Note:--prefix Prefix each log line with log source (pod and container names)

E.g.

k logs -f -l app-name=example-app --prefix

Note: hereapp-name=example-app label is on the pod. If you would like to stream logs from multiple pods from different application deployments within a namespace, then use a common label that’s present across all pods, or add a such label.

2. Stream logs of a particular container of a multi-containers pod with multiple replicas

k logs -f -l <pod-label-value> --prefix -c <container-name>

E.g.

k logs -f -l app-name=example-app --prefix -c example-conn

Note: hereapp-name=example-app label is on the pod, andexample-conn is the container name.

3. Stream logs of all containers of a multi-containers pod with multiple replicas

a. Using label

k logs -f -l <pod-label-value> --prefix -all-containers

E.g.

k logs -f -l app-name=example-app --prefix -all-containers

b. Using deployment name

k logs -f deploy/<deployment-name> --prefix -all-containers

E.g.

k logs -f deply/example-deployment --prefix -all-containers

4. Show labels associated with a pod

k get po <pod-name> --show-labels

5. Add label on running pod

k label po <pod-name> app-name=example-app

If you have reached here, then I made a satisfactory effort to keep you reading. Please be kind enough to leave any comments or ask for any corrections. Happy Kuberneting!