Add documentation for firewall requirements #512
Description
Is your feature request related to a problem?/Why is this needed
In the case of a network firewall, a list of domain names and ports used by the driver would speed up deployment time.
I'm trying to configure one now, and while I initially allow-listed the set of registries used, I'm also running into failures due to liveness probes, e.g.:
Failed to pull image "k8s.gcr.io/sig-storage/:v2.6.0": rpc error: code = Unknown desc = copying system image from manifest list: parsing image configuration: Get "https://prod-registry-k8s-io-us-east-2.s3.dualstack.us-east-2.amazonaws.com/containers/images/sha256:d2d60f42f3854ce69b063c75a6fee6099c973539531cef4147b1aa35a115e40b"
IOW, we need to add not only the k8s gcr registry, but also prod-registry-k8s-io-us-east-2.
Another complication are DNS aliases. For example, k8s.gcr.io is an alias for googlecode.l.googleusercontent.com
# nslookup k8s.gcr.io
Server: 127.0.0.1
Address: 127.0.0.1#53
Non-authoritative answer:
k8s.gcr.io canonical name = googlecode.l.googleusercontent.com.
Name: googlecode.l.googleusercontent.com
Address: 142.250.114.82
Name: googlecode.l.googleusercontent.com
Address: 2607:f8b0:4023:1002::52
/feature
Describe the solution you'd like in detail
Here's an OpenShift example as a guide:
https://docs.openshift.com/container-platform/4.13/installing/install_config/configuring-firewall.html