Image registry:
Kubernetes, as a container orchestration framework, requires images to launch containers. The image registry can be private or it can be one of the well know public registries.
Any access to images on registries such as docker, gcr, or AWS is outbound from the kube cluster and will likely require credentials. Outbound connectivity from the pods is given using well known Nameservers and gateway added through the master which even goes through the host visible network and to the external world. There are two modes for downloading images:
First, we can provide an insecure registry that is internal and private to the cluster. This registry has no images to begin with and all images can be subsequently uploaded to the registry. It helps us create a manifest of images required to host the application on the cluster and it provides us the ability to use non-tls registry
Second, we can use credentials with one or more external registries as add on because the outbound request for pulling an image can be configured using credentials by referring to them as “registry-creds". Each external registry can accept the path for a credentials file usually in json format which will help configure the registry.
Together these options allow all images to be made available inside the cluster so that containers can be spun up on the cluster to host the application.
Kubernetes has a controller-manager, a kubelet, an apiserver, a proxy, etcd and a scheduler. All of these can be configured using a configurator. The –feature-gates flag can be used to govern what can be allowed to run. The options supported by the feature-gates are few but the components can utilize them to provide selectivity in inclusion for running the app.
The images do not have feature gates. They are atomic and wholesome in that they are composed of layers but are treated as a whole image with <registry>/<name>:<tag> specifier. The images referenced as "repository" key value in the values file can simply specify the name and tag and utilize the registry resolving to locate the image. The kubernetes framework must be guided in this process.
Kubernetes, as a container orchestration framework, requires images to launch containers. The image registry can be private or it can be one of the well know public registries.
Any access to images on registries such as docker, gcr, or AWS is outbound from the kube cluster and will likely require credentials. Outbound connectivity from the pods is given using well known Nameservers and gateway added through the master which even goes through the host visible network and to the external world. There are two modes for downloading images:
First, we can provide an insecure registry that is internal and private to the cluster. This registry has no images to begin with and all images can be subsequently uploaded to the registry. It helps us create a manifest of images required to host the application on the cluster and it provides us the ability to use non-tls registry
Second, we can use credentials with one or more external registries as add on because the outbound request for pulling an image can be configured using credentials by referring to them as “registry-creds". Each external registry can accept the path for a credentials file usually in json format which will help configure the registry.
Together these options allow all images to be made available inside the cluster so that containers can be spun up on the cluster to host the application.
Kubernetes has a controller-manager, a kubelet, an apiserver, a proxy, etcd and a scheduler. All of these can be configured using a configurator. The –feature-gates flag can be used to govern what can be allowed to run. The options supported by the feature-gates are few but the components can utilize them to provide selectivity in inclusion for running the app.
The images do not have feature gates. They are atomic and wholesome in that they are composed of layers but are treated as a whole image with <registry>/<name>:<tag> specifier. The images referenced as "repository" key value in the values file can simply specify the name and tag and utilize the registry resolving to locate the image. The kubernetes framework must be guided in this process.
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