Update deployment labels using "kubectl patch" does not work - kubernetes

I am trying to update a label using kubectl.
When I use apply it works but it doesn't when doing a patch.
I tried kubectl patch deployment nginx-deployment --patch "$(cat nginx.yaml)"; it returns back no change where I would expect to get back a label change.
These are the only changes on my yaml.
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deployment
labels:
app: testLab
spec:
replicas: 3
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.8
ports:
- containerPort: 80
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deployment
labels:
app: helloWorld
spec:
replicas: 3
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.8
ports:
- containerPort: 80
Is there a restriction on what patch updates or it am I doing something wrong?
I also tried specifying --type strategic and other types but none seem to work.


After executing command kubectl patch on your second file (where you changed label) you should see following error:
Error from server: cannot restore map from string
After executing command kubectl apply on this file you should get following error :
error: error validating "nginx.yaml": error validating data: ValidationError(Deployment.metadata): unknown field "label" in io.k8s.apimachinery.pkg.apis.meta.v1.ObjectMeta; if you choose to ignore these errors, turn validation off with --validate=false
Your deployment file should looks like this:
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deployment
labels:
app: helloWorld
spec:
replicas: 3
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.8
ports:
- containerPort: 8
You missed to add space after app label.
Add space and then execute command kubectl patch deployment nginx-deployment --patch "$(cat nginx.yaml)" once again.
Here are useful documentations: labels-selectors, kubernetes-deployments, kubernetes-patch.


You should be having something like this in your metadata:
metadata:
name: nginx-deployment
labels:
label: testLabel2

Related

I am not able to create the pods with the below yaml query

apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deployment
labels:
app: nginx
spec:
selector:
matchLables:
app: nginx
replicas: 3
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: bginx:1.7.9
ports:
- containerPort: 80
error is:
error validating "app.yaml": error validating data: [ValidationError(Deployment.spec.selector): unknown field "matchLables" in io.k8s.apimachinery.pkg.apis.meta.v1.LabelSelector, ValidationError(Deployment.spec): unknown field "spec" in io.k8s.api.apps.v1.DeploymentSpec];

There is a typo in matchLables, it should be matchLabels. Additionally, you have the wrong indentation of spec.template.spec and of its content.
Something like the following example should work:
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deployment
labels:
app: nginx
spec:
selector:
matchLabels:
app: nginx
replicas: 3
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: bginx:1.7.9
ports:
- containerPort: 80

Error deploying a pod in a kubernetes cluster

I'm trying to deploy this yaml in my kubernetes cluster into one of my nodes
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deployment-1
labels:
app: nginx
spec:
replicas: 3
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx
ports:
- containerPort: 80
But when I try to deploy it with the command, I get this error message
pi#k8s-master-rasp4:~ $ kubectl apply -f despliegue-nginx.yaml -l kubernetes.io/hostname=k8s-worker-1
error: no objects passed to apply
Anyone knows where the problem could be?
Thanks

You are not allowed to use label selector (-l) with kubectl apply....
Use nodeSelector to assign pods to specific nodes:
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deployment-1
labels:
app: nginx
spec:
replicas: 3
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
nodeSelector:
kubernetes.io/hostname: k8s-worker-1 # <-- updated here!
containers:
- name: nginx
image: nginx
ports:
- containerPort: 80

Kubernetes: Is there a way to retrieve or inject local env vars into configmap.yaml? [duplicate]

I am setting up the kubernetes setup for django webapp.
I am passing environment variable while creating deployment as below
kubectl create -f deployment.yml -l key1=value1
I am getting error as below
error: no objects passed to create
Able to create the deployment successfully, If i remove the env variable -l key1=value1 while creating deployment.
deployment.yaml as below
#Deployment
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
labels:
service: sigma-service
name: $key1
What will be the reason for causing the above error while creating deployment?

I used envsubst (https://www.gnu.org/software/gettext/manual/html_node/envsubst-Invocation.html) for this. Create a deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: $NAME
labels:
app: nginx
spec:
replicas: 1
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.9
ports:
- containerPort: 80
Then:
export NAME=my-test-nginx
envsubst < deployment.yaml | kubectl apply -f -
Not sure what OS are you using to run this. On macOS, envsubst installed like:
brew install gettext
brew link --force gettext

This isn't a right way to use the deployment, you can't provide half details in yaml and half in kubectl commands. If you want to pass environment variables in your deployment you should add those detail in the deployment spec.template.spec:
You should add following block to your deployment.yaml
spec:
containers:
- env:
- name: var1
value: val1
This will export your environment variables inside the container.
The other way to export the environment variable is use kubectl run (not advisable) as it is going to be depreciated very soon. You can use following command:
kubectl run nginx --image=nginx --restart=Always --replicas=1 --env=var1=val1
The above command will create a deployment nginx with replica 1 and environment variable var1=val1

You cannot pass variables to "kubectl create -f". YAML files should be complete manifests without variables. Also you cannot use "-l" flag to "kubectl create -f".
If you want to pass environment variables to pod you should do like that:
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-deployment
labels:
app: nginx
spec:
replicas: 1
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.9
env:
- name: MY_VAT
value: MY_VALUE
ports:
- containerPort: 80
Read more here: https://kubernetes.io/docs/tasks/inject-data-application/define-environment-variable-container/

Follow the below steps
create test-deploy.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: MYAPP
labels:
app: nginx
spec:
replicas: 1
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.9
ports:
- containerPort: 80
using sed command you can update the deployment name at deployment time
sed -e 's|MYAPP|my-nginx|g' test-deploy.yaml | kubectl apply -f -

File: ./deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: MYAPP
labels:
app: nginx
spec:
replicas: 1
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.9
ports:
- containerPort: 80
File: ./service.yaml
apiVersion: v1
kind: Service
metadata:
name: MYAPP
labels:
app: nginx
spec:
type: ClusterIP
ports:
- port: 80
selector:
app: nginx
File: ./kustomization.yaml
resources:
- deployment.yaml
- service.yaml
If you're using https://kustomize.io/, you can do this trick in a CI:
sh '( echo "images:" ; echo " - name: $IMAGE" ; echo " newTag: $VERSION" ) >> ./kustomization.yaml'
sh "kubectl apply --kustomize ."

I chose yq since it is yaml aware and gives a precise control where text substitutions happen.
To set an image from bash env var:
export IMAGE="your_image:latest"
yq eval '.spec.template.spec.containers[0].image = "'$IMAGE'"' manifests/daemonset.yaml | kubectl apply -f -
yq is available on MacPorts (as of 19/04/21 v4.4.1) with sudo port install yq

I was facing the same problem. I created a python script to change simple/complex or add values to the YAML file.
This became very handy in a similar situation that you describe. Also, switching to the python domain can allow for more complex scenarios.
The code and how to use it are available at this gist.
https://gist.github.com/washraf/f81153270c80b0b4ecf90a53872abde7

Please try following
apiVersion: apps/v1
kind: Deployment
metadata:
namespace: kdpd00201
name: frontend
labels:
app: nginx
spec:
replicas: 6
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: frontend
image: ifccncf/nginx:1.14.2
ports:
- containerPort: 8001
env:
- name: NGINX_PORT
value: "8001"

My solution is then
apiVersion: apps/v1
kind: Deployment
metadata:
creationTimestamp: null
labels:
app: frontend
name: frontend
namespace: kdpd00201
spec:
replicas: 4
selector:
matchLabels:
app: frontend
strategy: {}
template:
metadata:
creationTimestamp: null
labels:
app: frontend
spec:
containers:
- env: # modified level
- name: NGINX_PORT
value: "8080"
image: lfccncf/nginx:1.13.7
name: nginx
ports:
- containerPort: 8080

kubectl apply -f ngx-dep.yaml error: error validating "ngx-dep.yaml": error validating data:

apiVersion: apps/v1
kind: Deployment
metadata:
name: ngx-dep3
labels:
app: ngx
type: webservice
spec:
replicas: 1
selector:
matchLabels:
app: ngx
template:
metadata:
labels:
app: ngx
spec:
containers:
- name: nginx
image: nginx:1.8
kubectl apply -f ngx-dep.yaml
error: error validating "ngx-dep.yaml": error validating data: [ValidationError(Deployment.spec.selector): unknown field "template" in io.k8s.apimachinery.pkg.apis.meta.v1.LabelSelector, ValidationError(Deployment.spec): missing required field "template" in io.k8s.api.apps.v1.DeploymentSpec]; if you choose to ignore these errors, turn validation off with --validate=false

Change identation. template should be on the same level with replicas, etc
spec:
replicas:
selector:
template:
Correct yaml:
apiVersion: apps/v1
kind: Deployment
metadata:
name: ngx-dep3
labels:
app: ngx
type: webservice
spec:
replicas: 1
selector:
matchLabels:
app: ngx
template:
metadata:
labels:
app: ngx
spec:
containers:
- name: nginx
image: nginx:1.8
kubectl apply -f a.yaml
deployment.apps/ngx-dep3 created
For mere information and example please refer to Deployment v1 apps official docs

Kubernetes replicaset creation using yaml file failed

When running command: kubectl create -f rs.yaml gives error
rs.yaml
kind: ReplicaSet
apiVersion: apps/v1
metadata:
name: myrs
spec:
replicas: 3
selector:
matchLabels:
app: rsexample
template:
metadata:
labels:
app: rsexample
spec:
containers:
- name: rscontainer
image: aamirpinger/helloworld:latest
ports:
- containerPort: 80
When running command:
kubectl create -f rs.yaml gives error
error: error parsing rs.yaml: error converting YAML to JSON: yaml: line 13: found character that cannot start any token

Its indentation issue, using tab instead of space(when replacing tab with space in line:13 error resolve)

Indentation is wrong in your yaml. Here is an example which works. Since you have uploaded an image rather the actual yaml it's not possible to fix your yaml in an answer.
apiVersion: apps/v1
kind: ReplicaSet
metadata:
name: frontend
labels:
app: guestbook
tier: frontend
spec:
# modify replicas according to your case
replicas: 3
selector:
matchLabels:
tier: frontend
template:
metadata:
labels:
tier: frontend #Look here
spec:
containers:
- name: php-redis
image: gcr.io/google_samples/gb-frontend:v3