Views:
To control all the Postfix computers from the web management console, enable the Apply settings to all scanners option. Choose Administrator → SMTP Routing → SMTP from the menu.

Can I make an exception on the settings for some Postfix instances separately?

To make an exception for some Postfix settings, search for the key "detach_key_postfix" in imss.ini, and add the keys that you do not want to apply from the web management console. For example:
detach_key_postfix=smtpd_use_tls:smtpd_enforce_tls:queue_directory
The parameters above will not be overwritten by any settings that you configure through the web console. You can modify main.cf manually.
Note
Note
“{Parameter1:{Parameter2}:…::{Parameter n}" means you can use one or more parameters by separating them using colons.
You can find the parameter names in the table tb_postfixconfig from the database, under the column fieldname.
WARNING
WARNING
Use extreme caution when modifying the configuration file.