Unable to pull from private docker hub registry on kubernetes - kubernetes

Question

I'm running a k8 cluster on google container engine. I'm having trouble getting it to pull images from a private docker repo.
I get the following when trying to boot:
Name: ds-expected-date
Namespace: default
Node: gke-ds-cluster-1-default-pool-8980b100-l64j/10.132.0.3
Start Time: Wed, 24 May 2017 13:24:11 +0100
Labels: <none>
Annotations: kubernetes.io/limit-ranger=LimitRanger plugin set: cpu request for container ds-expected-date-flask
Status: Pending
IP: 10.40.0.23
Controllers: <none>
Containers:
ds-expected-date-flask:
Container ID:
Image: fluidy/ds-expected-date:latest
Image ID:
Port:
State: Waiting
Reason: ImagePullBackOff
Ready: False
Restart Count: 0
Requests:
cpu: 100m
Environment: <none>
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from default-token-h340m (ro)
Conditions:
Type Status
Initialized True
Ready False
PodScheduled True
Volumes:
default-token-h340m:
Type: Secret (a volume populated by a Secret)
SecretName: default-token-h340m
Optional: false
QoS Class: Burstable
Node-Selectors: <none>
Tolerations: <none>
Events:
FirstSeen LastSeen Count From SubObjectPath Type Reason Message
--------- -------- ----- ---- ------------- -------- ------ -------
21s 21s 1 default-scheduler Normal Scheduled Successfully assigned ds-expected-date to gke-ds-cluster-1-default-pool-8980b100-l64j
18s 18s 1 kubelet, gke-ds-cluster-1-default-pool-8980b100-l64j spec.containers{ds-expected-date-flask} Normal BackOff Back-off pulling image "fluidy/ds-expected-date:latest"
18s 18s 1 kubelet, gke-ds-cluster-1-default-pool-8980b100-l64j Warning FailedSync Error syncing pod, skipping: failed to "StartContainer" for "ds-expected-date-flask" with ImagePullBackOff: "Back-off pulling image \"fluidy/ds-expected-date:latest\""
20s 6s 2 kubelet, gke-ds-cluster-1-default-pool-8980b100-l64j spec.containers{ds-expected-date-flask} Normal Pulling pulling image "fluidy/ds-expected-date:latest"
19s 5s 2 kubelet, gke-ds-cluster-1-default-pool-8980b100-l64j spec.containers{ds-expected-date-flask} Warning Failed Failed to pull image "fluidy/ds-expected-date:latest": Error response from daemon: unauthorized: authentication required
19s 5s 2 kubelet, gke-ds-cluster-1-default-pool-8980b100-l64j Warning FailedSync Error syncing pod, skipping: failed to "StartContainer" for "ds-expected-date-flask" with ErrImagePull: "Error response from daemon: unauthorized: authentication required"
I have followed all the instructions on the docs page. I'm confident my registry secret is being read - if I put duff credentials in it, the error changes to 'invalid user name or password'.

Answer 1

You have not configured your cluster to pull private images from Docker Hub with your credentials.
Read and apply this guide: https://kubernetes.io/docs/tasks/configure-pod-container/pull-image-private-registry/
Google Container Engine can automatically pull from Google Container Registry (http://gcr.io), consider using that without pulling images from a private registry.