Since I started with docker there is one question that follows me and I could not get a good answer so far.
Let's assume I have a .yaml file specifying a k8s deployment. We are building our docker images on a local build server and they are getting pushed to a local registry e.g. registry.mycompany.com which is only accesiable in our local company network. So in my .yaml I will reference that image with "image: registry.mycompany.com/myrepo/myimage:1.0".
Now when I deploy that on a local k8s cluster it works correctly as the domain name gets resolved and the image can be pulled. Now I want to deploy the same e.g. in any Cloud. Well, it wont work as the registry is not availiable. Same goes if I want to deploy the same .yaml at one of my customers places where they also for a good reason can not access my local registry.
How is this kind of thing solved usually? Right now, I setup another registry either at my customers or in the cloud account, retag all my images and push them to that registry and also change all the image references in the .yamls when I deploy at a customers place or in the cloud. Therefore having to maintain a lot of sets of files that are 99% the same. That is not how it should work right?
My "wish" would be that I can specify just the image name and tag "myimage:1.0" and the k8s cluster just checks all availiable registries if he can find the image and pulls it. But I am also aware that there is no "list of well-known-registries", you either specify the registry in the image name or leave it out and docker hub will be queried. However it would be very cool if I can specify just
apiVersion: extensions/v1beta1 kind: Deployment metadata: name: MyDeployment spec: replicas: 1 template: metadata: labels: app: myimage spec: containers: - name: myimage image: 'myimage:1.0' ports: 
and a list of registries:
registries: - registry.mycompany.com - registry.cloud.com - registry.localcustomer.com
But there is nothing like that, right?
The only other solution I can think of, is to build everything into helm charts, make the first part of the image reference a variable and pass the registry as a variable to the chart.
Any ideas and infos are welcome. Thanks in advance :)