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How to change the SMTP outgoing port from 25 to 26

eldhin

New Pleskian
Good day.

i want to ask, how can i change the outgoing SMTP port?. I want to change it to 26, since 25 is a port that some Internet Service Providers block

Thanks.
 
Are you really sure about this? If you change the port of your SMTP-Server you'll likely cannot send and receive E-Mails.
 
Hello,

Please check the following article:
https://kb.odin.com/en/837

==================

First a new entry will need to be created in xinetd for the alternate port:

cd /etc/xinetd.d

cp smtp_psa smtp_psa_p26

Next the entry that was just created needs to be modified:

vi smtp_psa_p26

Make the first line say “service smtp_p26” and save the file.

Next edit the services for the system to include the newly created one:

vi /etc/services

smtp_p26 26/tcp mail
smtp_p26 26/udp mail

After editing this, just restart xinetd and the server should be listening on port 26. A quick way to verify the changes took effect can be done using this command:

netstat -lpn|grep 26

NOTE: Don’t forget to make sure port 26 is open in the firewall.
==================

Thank you,
 
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