I have two clusters, one with Kubernetes 1.8.3-gke.0 and other with 1.7.8, both with the same secret key.

On 1.7.8 I push a deployment file to create a new pods from a private container on dockerhub. In that case I have no problem to pull the container successfully.

On the 1.8.3-gke.0 I do the same, push the exactly the same deployment file but in that case I get an error:

 Failed to pull image "some/container:latest": rpc error: code = Unknown desc = Error response from daemon: repository some/container not found: does not exist or no pull access
 Error syncing pod 

I cannot understand why this is happening, both are using the same secret key and same deployment file. Before I had the same problem on the 1.7.8, but by magic started working.

Thanks