Worker-pod Crashing, unable to start. (demo-voting-app)

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#1

Hi Team,

Need help in addressing issue with worker-pod which is part of demo-voting-app.

As checked from the cluster Below are the details for error.

Normal Started 7s (x3 over 24s) kubelet Started container worker-app
Warning BackOff 6s (x3 over 22s) kubelet Back-off restarting failed container

Logs:
kubectl logs worker-app-pod
System.NotSupportedException: Authentication method not supported (Received: 10)
at Npgsql.NpgsqlConnector.ParseServerMessage(ReadBuffer buf, BackendMessageCode code, Int32 len, DataRowLoadingMode dataRowLoadingMode, Boolean isPrependedMessage)
at Npgsql.NpgsqlConnector.DoReadMessage(DataRowLoadingMode dataRowLoadingMode, Boolean isPrependedMessage)
at Npgsql.NpgsqlConnector.ReadMessageWithPrepended(DataRowLoadingMode dataRowLoadingMode)
at Npgsql.NpgsqlConnector.HandleAuthentication(String username, NpgsqlTimeout timeout)
at Npgsql.NpgsqlConnector.Open(NpgsqlTimeout timeout)
at Npgsql.ConnectorPool.Allocate(NpgsqlConnection conn, NpgsqlTimeout timeout)
at Npgsql.NpgsqlConnection.OpenInternal()
at Worker.Program.OpenDbConnection(String connectionString) in /code/src/Worker/Program.cs:line 78
at Worker.Program.Main(String[] args) in /code/src/Worker/Program.cs:line 19

worker-app-prod.yaml
apiVersion: v1
kind: Pod
metadata:
name: worker-app-pod
labels:
name: worker-app-pod
app: demo-voting-app
spec:
containers:
- name: worker-app
image: kodekloud/examplevotingapp_worker:v1

Please check and advise, rest of the pods/service running without any issues except the worker-pod.

Thanks
Srini

Pod is crashing and backoff after getting started
#2

Hello @sri.lynx,
Please follow these full steps to know what you have missed and try again :

Note: We will create deployments again so please before following the steps, Run kubectl delete deployment --all to delete old deployments and avoid any conflicts.

  1. Run git clone https://github.com/mmumshad/example-voting-app-kubernetes-v2.git

  2. Run cd example-voting-app-kubernetes-v2/

  3. Run vim postgres-deployment.yml and modify it’s content as below then save and exit.

Note: It’s a new update from Postgres.

apiVersion: apps/v1
 kind: Deployment
 metadata:
   name: postgres-deployment
   labels:
     app: demo-voting-app
 spec:
   replicas: 1
   selector:
     matchLabels:
       name: postgres-pod
       app: demo-voting-app
   template:
     metadata:
       name: postgres-pod
       labels:
         name: postgres-pod
         app: demo-voting-app
     spec:
       containers:
       - name: postgres
         image: postgres:9.4
         env:
         - name: POSTGRES_USER
           value: postgres
         - name: POSTGRES_PASSWORD
           value: postgres
         - name: POSTGRES_HOST_AUTH_METHOD
           value: trust
         ports:
         - containerPort: 5432

  1. Run kubectl create -f . if you create deployments for the first time, if you created the same deployments before Run kubectl apply -f . .

  2. Run kubectl get service to get the exposed ports.

For example if the output of the command as above you can accces the voting app by hitting One_of_the_worker_nodes_IP:32733 on your browser and the same for the resulting app >> One_of_the_worker_nodes_IP:30013.

Check :

Note: The voting application only accepts one vote per client. It does not register votes if a vote has already been submitted from a client.

Hope this helps!

#3

Fantastic, Works fine. Just want to understand as far as worker-app-pod is concerned the image do not contain the tag information, does it means it’s taking up the latest one?

spec:
containers:
- name: worker-app
image: dockersamples/examplevotingapp_worker

Thanks
Srini

#4

yes, it will take the latest tag.