The "Debug peer level" option specifies the increment in verbose logging level when an SMTP client or server host name or address matches a pattern in the "Debug peer list" option. This option sets the "debug_peer_level" postfix variable.
The "Debug peer list" option specifies an optional list of domain or network patterns, /file/name patterns or type:name tables. When an SMTP client or server host name or address matches a pattern, increase the verbose logging level by the amount specified in the "Debug peer level" option. This option sets the "debug_peer_list" postfix variable.
The "Debugger command" option specifies the external command that is executed when a Postfix daemon program is run with the -D option.
Use "command .. & sleep 5" so that the debugger can attach before the process marches on. If you use an X-based debugger, be sure to set up your XAUTHORITY environment variable before starting Postfix. This option sets the "debugger_command" postfix variable.