We have a list of istioctl commands here that show whether they are supported or unsupported by the Sail Operator.

It has been decided by the team that:

1. Customers should only use our fork of istioctl.
2. Our fork of istioctl should return an error (code and message) when an unsupported command is attempted to be executed, and not execute it.
3. The error message should say (just at a high-level) why it is unsupported.
4. We will continue to maintain the table of supported and unsupported commands in the documentation.

This jira represents the work for points #2 and #3 above.