Switch to gcr.io endpoint that doesn't require auth.

[EricEdens]

Our build is currently failing with

ERRO[0000] Error while retrieving image from cache: marketplace.gcr.io/google/debian9 GET https://marketplace.gcr.io/v2/google/debian9/manifests/latest: UNAUTHORIZED: You don't have the needed permissions to perform this operation, and you may have invalid credentials. To authenticate your request, follow the steps in: https://cloud.google.com/container-registry/docs/advanced-authentication

Based on GoogleContainerTools/kaniko#659, one solution is to switch to an endpoint that doesn't require authentication. This endpoint that I'm using comes from the docs for managed images: https://github.com/GoogleContainerTools/base-images-docker/tree/master/debian

Testing:

I reproduced the issue locally by invoking kaniko directly. After switching to the new endpoint, the image was able to build.

[zoran15]

Our build is currently failing with

`ERRO[0000] Error while retrieving image from cache: marketplace.gcr.io/google/debian9 GET

Why did this start failing now? What base image did we use before?

[dntczdx]

LGTM

[EricEdens]

Our build is currently failing with
`ERRO[0000] Error while retrieving image from cache: marketplace.gcr.io/google/debian9 GET

Why did this start failing now? What base image did we use before?

Previously we used the image from docker hub:

https://github.com/GoogleCloudPlatform/compute-image-tools/blob/aa1cca8adc9530bf24a69e1b290a8d7dcf74127b/gce_vm_image_import.Dockerfile

Zach pointed me to GCP's managed base images: https://cloud.google.com/container-registry/docs/managed-base-images

[google-oss-robot]

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