Postfix Interview Questions & Answers part 1


Q: – What is the location of postfix mailserver Queue ?

By default, the Postfix mail queues are located in the /var/spool/postfix directory. Each message queue is created as a separate subdirectory within this directory. Each message is stored as a separate file in the subdirectory, using a unique identifier for the filename.

Q: – What is LMTP ?

The Local Mail Transport Protocol (LMTP) is a different mail transport protocol described in RFC 2033. LMTP utilizes a set protocol similar to SMTP for delivering messages to the local host. Postfix can be configured to deliver messages to local users using LMTP if desired.

Q: – What is canonical Table ?

The cleanup program uses the canonical table to rewrite message addresses contained in the message header. The mail administrator can use one canonical lookup table for both received messages and sent messages or separate tables for each. The canonical table is often used in conjunction with the alias file to provide address header rewriting of outgoing mail messages.

Q: – Who is the creater of Postfix ?

Wietse Venema wrote Postfix as a complete MTA package

Q: – What is the difference between postfix and sendmail ?

The main difference between Postfix and Sendmail is Postfix’s modularity. Just as the Unix system broke up e-mail functionality between modules, Postfix extends that practice to the MTA program. Postfix uses several different programs to implement the MTA functionality.This allows each modular program to be smaller and quicker than one large monolithic program would be.

Postfix is more secure than sendmail.Postfix requires a separate userid to be added to the mail server. Each module runs under this userid. If an intruder compro-mises a Postfix module, he most likely will still not be able to break out of the module and gain control of the mail server.

Instead of one large compiled configuration file, Postfix uses multiple files that use plaintext parameter and value names to define functionality. Most of the parameters used in Postfix default to common-sense values that allow the mail administrator to configure a complete mail server with a minimal amount of effort.

Q: – what is qmgr ?

Once the valid message is rewritten and placed in the incoming message queue, the qmgr program ensures that the message is delivered to the proper destinations. The qmgr program then examines message headers and passes them to the appropriate delivery program depending on the destination addresses. Currently, the qmgr program can forward messages to the local, smtp, and pipe programs.

Q: – Tell me about latest Version of Postfix on which u have worked ?

postfix 2.6

Q: – What are the important files for postfix server ?


Q: – Where postfix mail server logs created ?


Submitted By:-Swati Rana           Email-ID: –