What are 'Access Hosts' in a MySQL database?

Question

I'm setting up a MySQL database, and there's an option about 'access hosts'. What are they and what do they do?

Answer 1

It's a list of external hosts (or remote MySQL servers) that are allowed access to your database. It's just another form of access control, but this time based on the domain name of a host hoping to access your DB.

At the very least, there should be one entry for 'localhost' - i.e., a server running on the local machine.