radosgw-admin user create error message is confusing if user with supplied email address already exists
If you try and create an S3 user account with an email address that's already in use, you get a very confusing error message.
Suppose that bar@domain is already in use for an S3 account uid=baz
radosgw-admin user create --uid=foo --display-name=Foo --email=bar@domain
will return something like:
could not create user: unable to parse parameters, user id mismatch, operation id: baz does not match: foo
...which is pretty confusing.
I think I have a patch to make the error message more helpful, but thought I should put in a tracker issue in the mean time. I found this in Luminous, but it's still present in master.