Email Tutorials - Herong's Tutorial Examples

∟Postfix - Mail Transport Agent (MTA)

∟"postconf" Command to Manage Postfix Configuration

This section provides a tutorial example on how to 'postconf' command to manage Postfix configuration settings.

The "postconf" command provided by the Postfix package can be used to manage Postfix configuration settings.

1. Use "postconf" command to display current Postfix main.cf settings. 

herong$ postconf | more

2bounce_notice_recipient = postmaster
access_map_defer_code = 450
access_map_reject_code = 554
address_verify_cache_cleanup_interval = 12h
address_verify_default_transport = $default_transport
address_verify_local_transport = $local_transport
address_verify_map = btree:$data_directory/verify_cache
address_verify_negative_cache = yes
address_verify_negative_expire_time = 3d
address_verify_negative_refresh_time = 3h
address_verify_pending_request_limit = 5000
...

2. Use "postconf -d" command to display original default Postfix main.cf settings. 

herong$ postconf -d | grep size_limit
mailbox_size_limit = 51200000
message_size_limit = 10240000

herong$ postconf | grep size_limit
mailbox_size_limit = 1024000000
message_size_limit = 102400000

3. Use "postconf -e parameter=value" command to change a Postfix master.cf setting. 

herong$ sudo postconf -e message_size_limit=1024000001

herong$ postconf | grep message_size_limit
message_size_limit = 1024000001

4. Use "postconf -Mf" command to display Postfix master.cf settings. 

herong$ postconf -Mf | more

smtp       inet  n       -       n       -       -       smtpd
submission inet  n       -       n       -       -       smtpd
    -o syslog_name=postfix/submission
    -o smtpd_tls_security_level=may
smtps      inet  n       -       n       -       -       smtpd
    -o syslog_name=postfix/smtps
    -o smtpd_tls_wrappermode=yes
    -o smtpd_sasl_auth_enable=yes
pickup     unix  n       -       n       60      1       pickup
cleanup    unix  n       -       n       -       0       cleanup
qmgr       unix  n       -       n       300     1       qmgr
tlsmgr     unix  -       -       n       1000?   1       tlsmgr
...

Table of Contents

 About This Book

 Introduction to Email

►Postfix - Mail Transport Agent (MTA)

 What Is Postfix

 Install and Configure Postfix on CentOS

 Test Postfix Server with "telnet" Client

 SMTP Submission Service on Port 587 in Postfix

 Archive Emails using "always_bcc" Setting in Postfix

 Move /var/spool/postfix to New Location

►"postconf" Command to Manage Postfix Configuration

 Turn on Postfix Server Logging for Troubleshooting

 SSL/TLS Secure Connections with Postfix Server

 Dovecot - IMAP and POP3 Server

 SSL/TLS Secure Connections with Dovecot Server

 Email Client Tools - Mail User Agents (MUA)

 Mozilla Thunderbird - Mail User Agents (MUA)

 References

 Full Version in PDF/EPUB