Search

Language:  
Search for:

Available article translations:

Can I use an additional port other than port 25 for SMTP connections? I was told I should open up one more ports for SMTP because most ISPs block port 25 now.

APPLIES TO:
  • Parallels Plesk for Linux/Unix
  • Parallels Plesk 12.0 for Windows
  • Parallels Plesk 10.1 for Windows

Symptoms

Can I use an additional port other than port 25 for SMTP connections? I was told I should open up more ports for SMTP because most ISPs block port 25 now.

Resolution

(Parallels Plesk Panel 9.5.x - 11.x)

By default, Parallels Plesk Panel (Plesk) 11 accepts mail submission on TCP port 587.

Open Tools & Settings > Mail Server Settings (in the Mail group). Select the Enable message submission checkbox

We recommend that you use the Plesk web interface to configure the Postfix Submission port. If you configure the SMTP submission port directly in MTA, the setting can be overwritten by Plesk.

Follow the instructions below to configure an additional SMTP port for your MTA:

QMail (Parallels Plesk Panel 8.x, 9.x)

Choose any unused port and add it to the /etc/services file. For example:

  smtp_alt 25025/tcp # new SMTP port  

If you have 'xinetd' as a super-server, make a copy of /etc/xinetd.d/smtp_psa to /etc/xinetd.d/smtp_psa_alt and correct the service line within the new file:

service smtp_alt

Restart xinetd /etc/init.d/xinetd restart and the SMTP connections will be accepted on both the standard and 25025 ports. You may also need to reconfigure Horde IMP (webmail) settings so they use the alternative SMTP port. This can be done in the /etc/psa-horde/imp/servers.php file under the smtpport parameter for both IMAP and POP3 servers.

If you have a 'netd' super-server (Debian or FreeBSD), modify inetd.conf to enable an additional SMTP port:

grep '^smtp ' /etc/inetd.conf | sed 's/^smtp/smtp_alt/' >> /etc/inetd.conf

and restart inetd.

NOTE: If you want to disable the default (25) port completely and only use an alternate one, please do not block port 25 at the firewall and do not remove the smtp_psa service from the xinetd/inetd. Instead, set the default SMTP service to be listened only on 127.0.0.1 by adding bind = 127.0.0.1 to /etc/xinetd.d/smtp_psa. Otherwise, the SMTP service status will be displayed incorrectly in the Plesk control panel. Plesk determines SMTP service status by checking the 25th port and the port number is hardcoded there.

Postfix (Parallels Plesk Panel 9.x, 10.x, ...)

Add the following line to the Postfix configuration file /etc/postfix/master.cf:

<IP_Address>:<port> inet n - n - - smtpd

where <IP_Address> is the IP address of your server and <port> is the additional port for the SMTP connection.

If Postfix is configured to use Postfix Before-Queue Content Filter extend the line with the proxy filter settings:

<IP_Address>:<port> inet n - - - - smtpd -o smtpd_proxy_filter=127.0.0.1:10025

Reload the mail service with mailmng after the reconfiguration:

# /usr/local/psa/admin/sbin/mailmng --reload-service
Reloading postfix: [  OK  ]

Search words:

Must issue a STARTTLS command first

port 25 is blocked

smtp server issue

not working 587 port

MTA

port 587

SMTP-MSA

Message submission

smtp alternate port

sasl

mail




56797cefb1efc9130f7c48a7d1db0f0c c81e59b61af9dca603ba03b14aabe968 9f8baf78266b4e54525d1c6bf06305a5 6c940ecb931cefd4545ee0d1db669dd5 42844a8183c58f5bd71c7d59929707e6 e26cd5a43fdb23cb2c65dd477ab20f95 4bd416dd9da208376c20e13782bef971 230ec28618f20889fbaa0a73287fbabb

FEEDBACK
Was this article helpful?
Tell us how we may improve it.
Yes No
 
 
 
 
 
 
Desktop Virtualization
- Parallels Desktop 9 for Mac
- Parallels Transporter
- Parallels Desktop Switch to Mac Edition
- Parallels Desktop for Mac Enterprise Edition
- Parallels Management-Mac for Microsoft SCCM
Server Virtualization
- Parallels Cloud Server
- Parallels Containers for Windows 6.0 Beta
- Parallels Virtuozzo Containers
Automation
- Parallels Automation
- Parallels Automation for Cloud Infrastructure
- Parallels Business Automation Standard
- Parallels Virtual Automation
- Parallels Plesk Panel Suite
- Web Presence Builder
- Parallels Plesk Automation
- Parallels Small Business Panel
- Value-added Services for Hosters
- Parallels Partner Storefront
Services & Resources
- Cloud Acceleration Services
- Professional Services
- Support Services
- Training & Certification