Disallowed domains defaults and when to use the setting

[timkgh]

1. What is the story behind the disallowed domains out of the box defaults version.bind, id.server, hostname.bind?

2. If I want to block some domains and all their subdomains, should I use "Disallowed domains" or "Custom filtering rules"?

[ameshkov]

What is the story behind the disallowed domains out of the box defaults version.bind, id.server, hostname.bind?

They are often used by different scanners to check if there's an open resolver.

If I want to block some domains and all their subdomains, should I use "Disallowed domains" or "Custom filtering rules"?

You should use custom filtering rules.

Disallowed domains purpose is to protect public resolvers from abuse.