> ## Content Index > Fetch the complete content index at: https://www.hackerstack.org/llms.txt > Use this file to discover other available public pages before exploring further. # Practical Kubernetes Tips for Everyday Ops - URL: https://www.hackerstack.org/practical-kubernetes-tips-for-everyday-ops/ - Published: 2026-10-21T13:00:34.000Z - Updated: 2026-10-21T13:00:48.000Z - Description: A set of practical Kubernetes tips (or how-tos) that may help you in your day-to-day operations. Formating outputs, filtering objects, waiting for pods and more. - Author: Gmkziz 👓 - Tags: DevOps ### Formating outputs #### Listing resources Here is an example `kubectl` command to list resource of type pod: ``` $ kubectl -n kube-system get pods NAME READY STATUS RESTARTS AGE coredns-7d764666f9-q7mlf 1/1 Running 0 17m etcd-minikube 1/1 Running 0 17m kube-apiserver-minikube 1/1 Running 0 17m kube-controller-manager-minikube 1/1 Running 0 17m kube-proxy-6p24v 1/1 Running 0 17m kube-scheduler-minikube 1/1 Running 0 17m storage-provisioner 1/1 Running 1 (16m ago) 17m ``` This is the default output. You can use the `-o` flag to change the output format. For help about using that flag, run `kubectl get --help` and look for the flag in the **Options** section or look at formating outputs examples in the **Examples** section. #### Output only resources names To only output the `NAME` column run: ``` $ kubectl -n kube-system get pods -o NAME pod/coredns-7d764666f9-q7mlf pod/etcd-minikube pod/kube-apiserver-minikube pod/kube-controller-manager-minikube pod/kube-proxy-6p24v pod/kube-scheduler-minikube pod/storage-provisioner ``` #### Output additional info To show additional info like pods IP addresses and nodes names for instance, use: ``` $ kubectl -n kube-system get pods -o wide NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES coredns-7d764666f9-q7mlf 1/1 Running 0 28m 10.244.0.2 minikube etcd-minikube 1/1 Running 0 28m 192.168.49.2 minikube kube-apiserver-minikube 1/1 Running 0 28m 192.168.49.2 minikube kube-controller-manager-minikube 1/1 Running 0 28m 192.168.49.2 minikube kube-proxy-6p24v 1/1 Running 0 28m 192.168.49.2 minikube kube-scheduler-minikube 1/1 Running 0 28m 192.168.49.2 minikube storage-provisioner 1/1 Running 1 (27m ago) 28m 192.168.49.2 minikube ``` #### Show labels To show labels in the output, you can use: ``` $ kubectl -n kube-system get pods --show-labels NAME READY STATUS RESTARTS AGE LABELS coredns-7d764666f9-n2pxg 1/1 Running 0 6m20s k8s-app=kube-dns,pod-template-hash=7d764666f9 etcd-minikube 1/1 Running 0 6m25s component=etcd,tier=control-plane kube-apiserver-minikube 1/1 Running 0 6m25s component=kube-apiserver,tier=control-plane kube-controller-manager-minikube 1/1 Running 0 6m25s component=kube-controller-manager,tier=control-plane kube-proxy-5zlr9 1/1 Running 0 6m20s controller-revision-hash=9b7b96d6c,k8s-app=kube-proxy,pod-template-generation=1 kube-scheduler-minikube 1/1 Running 0 6m27s component=kube-scheduler,tier=control-plane storage-provisioner 1/1 Running 1 (5m49s ago) 6m23s addonmanager.kubernetes.io/mode=Reconcile,integration-test=storage-provisioner ``` #### Customize output columns You can also customize the column that are shown in the output. Here is an example: ``` $ kubectl get pods -n kube-system -o custom-columns=NAME:.metadata.name,NAMESPACE:.metadata.namespace NAME NAMESPACE coredns-7d764666f9-q7mlf kube-system etcd-minikube kube-system kube-apiserver-minikube kube-system kube-controller-manager-minikube kube-system kube-proxy-6p24v kube-system kube-scheduler-minikube kube-system storage-provisioner kube-system ``` You could also use a custom columns template file instead of specifying the custom columns in the command. Here is an equivalent template file (`template.txt`) content for the preceding output: ``` NAME NAMESPACE metadata.name metadata.namespace ``` To use the template file to format the output, run: ``` $ kubectl -n kube-system get pods -o custom-columns-file=template.txt NAME NAMESPACE coredns-7d764666f9-q7mlf kube-system etcd-minikube kube-system kube-apiserver-minikube kube-system kube-controller-manager-minikube kube-system kube-proxy-6p24v kube-system kube-scheduler-minikube kube-system storage-provisioner kube-system ``` #### Output JSON and YAML You can also output info about resources using YAML or JSON formats. Here are example commands: ``` # Only showing the first 20 lines of the outputs $ kubectl -n kube-system get pods etcd-minikube -o json | head -n 20 { "apiVersion": "v1", "kind": "Pod", "metadata": { "annotations": { "kubeadm.kubernetes.io/etcd.advertise-client-urls": "https://192.168.49.2:2379", "kubernetes.io/config.hash": "5ff8e3b06bbaa8cb7ebc2bf531e48a2f", "kubernetes.io/config.mirror": "5ff8e3b06bbaa8cb7ebc2bf531e48a2f", "kubernetes.io/config.seen": "2026-07-29T05:53:15.399573935Z", "kubernetes.io/config.source": "file" }, "creationTimestamp": "2026-07-29T05:53:15Z", "generation": 1, "labels": { "component": "etcd", "tier": "control-plane" }, "name": "etcd-minikube", "namespace": "kube-system", "ownerReferences": [ $ kubectl -n kube-system get pods etcd-minikube -o yaml | head -n 20 apiVersion: v1 kind: Pod metadata: annotations: kubeadm.kubernetes.io/etcd.advertise-client-urls: https://192.168.49.2:2379 kubernetes.io/config.hash: 5ff8e3b06bbaa8cb7ebc2bf531e48a2f kubernetes.io/config.mirror: 5ff8e3b06bbaa8cb7ebc2bf531e48a2f kubernetes.io/config.seen: "2026-07-29T05:53:15.399573935Z" kubernetes.io/config.source: file creationTimestamp: "2026-07-29T05:53:15Z" generation: 1 labels: component: etcd tier: control-plane name: etcd-minikube namespace: kube-system ownerReferences: - apiVersion: v1 controller: true kind: Node ``` #### Output only specific objects fields To show info only from specific fields of the previous JSON or YAML outputs you can use the following command: ``` $ kubectl -n kube-system get pods etcd-minikube -o jsonpath={.metadata.creationTimestamp} 2026-07-29T05:53:15Z ``` ### Filtering objects #### Using labels You can filter Kubernetes objects through their labels as follows: ``` $ kubectl get pods -n kube-system -l k8s-app=kube-dns NAME READY STATUS RESTARTS AGE coredns-7d764666f9-9hmxc 1/1 Running 0 2m45s ``` You can specify multiple filtering labels (`key=value`) by separating them with commas or specifying the `-l` or `--selector` flag multiple times. Only resources matching all the specified labels will be shown. #### Using objects fields ##### Overview You can also filter objects through specific objects fields. Here is for instance a truncated JSON of a pod: ``` $ kubectl get pods -n kube-system coredns-7d764666f9-9hmxc -o yaml | head -n 10 apiVersion: v1 kind: Pod metadata: creationTimestamp: "2026-08-06T06:33:32Z" generateName: coredns-7d764666f9- generation: 1 labels: k8s-app: kube-dns pod-template-hash: 7d764666f9 name: coredns-7d764666f9-9hmxc (...) ``` You can filter pods resources to only show the pod above by using a specific field inside its JSON as follows: ``` $ kubectl get pods -n kube-system --field-selector metadata.name=coredns-7d764666f9-9hmxc NAME READY STATUS RESTARTS AGE coredns-7d764666f9-9hmxc 1/1 Running 0 8m57s ``` Only a limited set of objects fields are supported by the `--field-selector` flag. ##### Filtering events Here are examples for filtering events: ``` # Get eventsonly for a specific Pod $ kubectl -n kube-system get events --field-selector=involvedObject.name=coredns-7d764666f9-rhktv LAST SEEN TYPE REASON OBJECT MESSAGE 2m56s Normal Scheduled pod/coredns-7d764666f9-rhktv Successfully assigned kube-system/coredns-7d764666f9-rhktv to minikube 2m55s Normal Pulled pod/coredns-7d764666f9-rhktv Container image "registry.k8s.io/coredns/coredns:v1.13.1" already present on machine and can be accessed by the pod 2m55s Normal Created pod/coredns-7d764666f9-rhktv Container created 2m55s Normal Started pod/coredns-7d764666f9-rhktv Container started 2m31s Warning Unhealthy pod/coredns-7d764666f9-rhktv Readiness probe failed: HTTP probe failed with statuscode: 503 # Get only events of type Warning for that Pod $ kubectl -n kube-system get events --field-selector=involvedObject.name=coredns-7d764666f9-rhktv,type=Warning LAST SEEN TYPE REASON OBJECT MESSAGE 7m1s Warning Unhealthy pod/coredns-7d764666f9-rhktv Readiness probe failed: HTTP probe failed with statuscode: 50 ``` To see events object fields to know which ones you can use for selection, use the JSON output. Here is an example truncated output: ``` $ kubectl -n kube-system get events -o json | head -n 40 { "apiVersion": "v1", "items": [ { "apiVersion": "v1", "count": 1, "eventTime": null, "firstTimestamp": "2026-08-07T22:24:17Z", "involvedObject": { "apiVersion": "v1", "kind": "Pod", "name": "coredns-7d764666f9-rhktv", "namespace": "kube-system", "resourceVersion": "353", "uid": "dda3f0b7-546d-41fb-9354-c3c80cc9b713" }, "kind": "Event", "lastTimestamp": "2026-08-07T22:24:17Z", "message": "Successfully assigned kube-system/coredns-7d764666f9-rhktv to minikube", "metadata": { "creationTimestamp": "2026-08-07T22:24:17Z", "name": "coredns-7d764666f9-rhktv.18c9a63131d82df5", "namespace": "kube-system", "resourceVersion": "357", "uid": "9e75e6ba-df73-4d0c-8c09-6e2ffb8d9a68" }, "reason": "Scheduled", "reportingComponent": "default-scheduler", "reportingInstance": "", "source": { "component": "default-scheduler" }, "type": "Normal" }, { "apiVersion": "v1", "count": 1, "eventTime": null, "firstTimestamp": "2026-08-07T22:24:18Z", "involvedObject": { (...) ``` ##### Filtering pods by status Use the `status.phase` objects field for that. Will have the following values: - `Running` \- for running pods - `Failed` \- for failed pods ``` # Only list pods with Running status kubectl get pods -n mynamspace --field-selector status.phase=Running # Only list pods in error kubectl get pods -n mynamspace --field-selector status.phase=Failed ``` ### Waiting for pods Imagine you have scaled down a deployment for instance and want to be sure that all the deployment pods are properly deleted before scaling up. You can use the following command to wait for pods to be deleted: ``` # By name kubectl -n mynamespace wait --for=delete pod/myapp --timeout=60s # By labels kubectl -n mynamespace wait --for=delete pod -l app.kubernetes.io/name=myapp --timeout=60s ``` When waiting for a bunch of pods with same labels, if jobs pods are part of the selection, the wait will not succeed. To filter out jobs pods (succeeded ones for isntance), use the `--field-selector` flag as follows: ``` kubectl -n mynamespace wait --for=delete pod -l app.kubernetes.io/name=myapp --field-selector status.phase!=Succeeded --timeout=60s ``` You can also wait for a specific pod condition (Ready for instance) as follows: ``` kubectl -n mynamespace wait --for=condition=Ready=True pod -l app.kubernetes.io/name=myapp --field-selector status.phase!=Succeeded --timeout=60s ``` ### Other stuff #### Adding a single file into containers FS using volumes ``` (...) volumes: - name: app-config configMap: name: app-config items: # we want the file inside the container to be called .env - key: config.env path: .env containers: - name: app volumeMounts: - name: app-config mountPath: /app/config/.env subPath: .env # this creates the /app/config/.env and keep the old files ``` Here is the result: ``` #----------------------# # With 'subPath: .env' # #----------------------# /app $ ls -lah config/ total 24K drwxr-xr-x 1 www-data www-data 4.0K Oct 10 14:59 . drwxr-xr-x 1 www-data www-data 4.0K Oct 9 15:07 .. -rw-r--r-- 1 root www-data 377 Oct 10 14:59 .env # <= a file -rwxr-xr-x 1 www-data www-data 3.0K Oct 9 15:07 config.inc.php -rwxr-xr-x 1 www-data www-data 629 Oct 9 15:07 config_env.php # Accessing the mounted file /app $ cat config/.env MYVAR=VALUE #-------------------------# # Without 'subPath: .env' # #-------------------------# /app $ ls -lah config/ total 24K drwxr-xr-x 1 www-data www-data 4.0K Oct 10 15:13 . drwxr-xr-x 1 www-data www-data 4.0K Oct 9 15:07 .. drwxrwsrwx 3 root www-data 4.0K Oct 10 15:13 .env # <= a directory -rwxr-xr-x 1 www-data www-data 3.0K Oct 9 15:07 config.inc.php -rwxr-xr-x 1 www-data www-data 629 Oct 9 15:07 config_env.php # Accessing the mounted file /app $ cat config/.env/.env MYVAR=VALUE ``` --- Want to report a mistake or ask questions ? Feel free to email me at [gmkziz@hackerstack.org](mailto:gmkziz@hackerstack.org). I will be glad to answer. If you like my articles, consider registering to my newsletter in order to receive the latest posts as soon as they are available. Take care, keep learning and see you in the next post 🚀