This appendix contains an alphabetical listing of parameters normally configured in the Postfix main.cf file. The brief descriptions are only meant to give you an idea of the purpose of the parameter. All of the parameters are fully documented in the sample configuration files and manpages that come with the Postfix distribution. This quick reference can point you in the right direction, but you will have to consult the body of this book or the online documentation to understand how each parameter works.
All of the parameters are listed with a type of value that should be assigned to it. Most of the value types are obvious. Those that require some explanation are described here:
The parameter requires one or more items from a specific list of possible values. See the online documentation for a particular parameter to see what the possible values are.
When a parameter points to lookup tables, the tables are specified with their map type and the table name separated by a colon:
transport_map = hash:/etc/postfix/transport
The complete path to a file.
Some parameter values are specified as strings that contain macros:
smtpd_banner = $myhostname ESMTP $mail_name
The macros are expanded into their values at the time the parameter is used. See the online documentation to find out what macros are allowed for a particular template parameter.
Many parameters are specified as an amount of time: