Plesk is middleware between end users and external services such as FTP, mail, DNS and others. Due to technical limitations, Plesk is able to interact with these services only if they are available on certain ports.

The list below provides information about services managed through Plesk and about ports on which they should be available for proper interaction with Plesk. If you use a firewall, make sure that the connections to all of these ports are allowed for corresponding Plesk services.

Service name Ports used by service
Administrative interface of Plesk over HTTPS TCP 8443
Administrative interface of Plesk over HTTP TCP 8880
Web server TCP 80, TCP 443
FTP server TCP 21
SSH (secure shell) server TCP 22
SMTP (mail sending) server TCP 25, TCP 465
POP3 (mail retrieval) server TCP 110, TCP 995
IMAP (mail retrieval) server TCP 143, TCP 993
MySQL server TCP 3306
MS SQL server TCP 1433
PostgreSQL server TCP 5432
Licensing Server connections TCP 443
Domain name server UDP 53, TCP 53
Plesk upgrades and updates TCP 8447

Note: If you install Presence Builder as part of Plesk, Presence Builder uses the same protocol and opens on the same port as the Plesk UI.