Postfix/main.cf/virtual mailbox maps

• parameter: virtual_mailbox_maps
• default: (empty)

About

Optional lookup tables with all valid addresses in the domains that match $virtual_mailbox_domains.

In a lookup table, specify a left-hand side of "@domain.tld" to match any user in the specified domain that does not have a specific "user@domain.tld" entry.

The virtual(8) delivery agent uses this table to look up the per-recipient mailbox or maildir pathname. If the lookup result ends in a slash ("/"), maildir-style delivery is carried out, otherwise the path is assumed to specify a UNIX-style mailbox file. Note that $virtual_mailbox_base is unconditionally prepended to this path.

When a recipient address has an optional address extension (user+foo@domain.tld), the virtual(8) delivery agent looks up the full address first, and when the lookup fails, it looks up the unextended address (user@domain.tld).

Note 1: for security reasons, the virtual(8) delivery agent disallows regular expression substitution of $1 etc. in regular expression lookup tables, because that would open a security hole.

Note 2: for security reasons, the virtual(8) delivery agent will silently ignore requests to use the proxymap(8) server. Instead it will open the table directly. Before Postfix version 2.2, the virtual(8) delivery agent will terminate with a fatal error.