Where are created mailboxes added under ISP?

I would like to know where are mailbox settings created under ISP? Somewhere in Postfix? I saw /var/vmail directory but there are only mailboxes with specific directories belonging to them but no idea where are settings.

 

Thank you till for answer. But how postfix know about them? I mean, if I would like to create mailbox without using ISP, how could I do it?

 

postfix has plugins which allow database lookups, these are defined in main.cf , see mysql_virtual*something files in /etc/postfix, too

 

Of course I don't want to do this on ISP server. I am just curious.

Thank you, I am going to check it.
EDIT
I have checked and in /etc/postfix/main.cf are few lines with "mysql-virtual" string:

Code:

virtual_alias_domains =
virtual_alias_maps = hash:/var/lib/mailman/data/virtual-mailman, proxy:mysql:/etc/postfix/mysql-virtual_forwardings.cf, proxy:mysql:/etc/postfix/mysql-virtual_email2email.cf
virtual_mailbox_domains = proxy:mysql:/etc/postfix/mysql-virtual_domains.cf
virtual_mailbox_maps = proxy:mysql:/etc/postfix/mysql-virtual_mailboxes.cf
virtual_mailbox_base = /var/vmail
virtual_uid_maps = mysql:/etc/postfix/mysql-virtual_uids.cf
virtual_gid_maps = mysql:/etc/postfix/mysql-virtual_gids.cf
sender_bcc_maps = proxy:mysql:/etc/postfix/mysql-virtual_outgoing_bcc.cf
[...]

so it looks like each .cf file contains some database entries. What about files with tilde at the end of file name, like .cf~ ? I have few there.

 

these are backup copies of previous version ( generated on updating / reconfigure of services )

 

Mhm, so I can remove them safetly. There is a lot these files. No idea why that much.