What ports should be open on a WHM/cPanel server?

by Michael Cannon in Featured, Server · 0 comments

Sometimes, it’s confusing which server ports should be open when setting up a server. Hopefully, this introduction to the ports that I generally keep open on a WHM/cPanel server running web, database, email, etc. services will help. Within WHM/cPanel I use the ConfigServer Security & Firewall script to manage my firewall port access and server security.

Do keep in mind to only have the ports open that you need. If you’re not needing or running a particular service, turn off that service and disable the port.

Incoming TCP Ports

Port	TCP	UDP	Description	Status
20	TCP	UDP	FTP—data transfer	Official
21	TCP	UDP	FTP—control (command)	Official
22	TCP	UDP	Secure Shell (SSH)—used for secure logins, file transfers (scp, sftp) and port forwarding	Official
25	TCP		Simple Mail Transfer Protocol (SMTP)—used for e-mail routing between mail servers	Official
26	TCP	UDP	Unassigned, often used as alternate SMTP	Official
53	TCP	UDP	Domain Name System (DNS)	Official
80	TCP	UDP	Hypertext Transfer Protocol (HTTP)	Official
110	TCP		Post Office Protocol v3 (POP3)	Official
143	TCP		Internet Message Access Protocol (IMAP)—management of email messages	Official
443	TCP		HTTPS (Hypertext Transfer Protocol over SSL/TLS)	Official
465	TCP		SMTP over SSL	Unofficial
953	TCP	UDP	Domain Name System (DNS) RNDC Service	Unofficial
993	TCP		Internet Message Access Protocol over SSL (IMAPS)	Official
995	TCP		Post Office Protocol 3 over TLS/SSL (POP3S)	Official
2077	TCP		Webdisk	Unofficial
2078	TCP		Webdisk SSL	Unofficial
2082	TCP		CPanel default	Unofficial
2083	TCP		CPanel default SSL	Unofficial
2086	TCP		WebHost Manager default	Unofficial
2087	TCP		WebHost Manager default SSL	Unofficial
2095	TCP		CPanel default Web mail	Unofficial
2096	TCP		CPanel default SSL Web mail	Unofficial
30000:35000	TCP		Needed pure-ftpd enabled PASV	Unofficial

Outgoing TCP Ports

Port	TCP	UDP	Description	Status
20	TCP	UDP	FTP—data transfer	Official
21	TCP	UDP	FTP—control (command)	Official
22	TCP	UDP	Secure Shell (SSH)—used for secure logins, file transfers (scp, sftp) and port forwarding	Official
25	TCP		Simple Mail Transfer Protocol (SMTP)—used for e-mail routing between mail servers	Official
37	TCP	UDP	TIME protocol	Official
43	TCP		WHOIS protocol	Official
53	TCP	UDP	Domain Name System (DNS)	Official
80	TCP	UDP	Hypertext Transfer Protocol (HTTP)	Official
110	TCP		Post Office Protocol v3 (POP3)	Official
113	TCP	UDP	ident—Authentication Service/Identification Protocol, used by IRC servers to identify users	Official
143	TCP		Internet Message Access Protocol (IMAP)—management of email messages	Official
443	TCP		HTTPS (Hypertext Transfer Protocol over SSL/TLS)	Official
587	TCP		e-mail message submission (SMTP)	Official
873	TCP	UDP	rsync file synchronisation protocol	Official USA only
995	TCP		Post Office Protocol 3 over TLS/SSL (POP3S)	Official
2087	TCP		WebHost Manager default SSL	Unofficial
2089	TCP		cPanel License Update	Unofficial
2703	TCP		2703 Razor email scanning	Unofficial

Incoming UDP Ports

Port	TCP	UDP	Description	Status
20	TCP	UDP	FTP—data transfer	Official
21	TCP	UDP	FTP—control (command)	Official
53	TCP	UDP	Domain Name System (DNS)	Official

Outgoing UDP Ports

Port	TCP	UDP	Description	Status
20	TCP	UDP	FTP—data transfer	Official
21	TCP	UDP	FTP—control (command)	Official
53	TCP	UDP	Domain Name System (DNS)	Official
113	TCP	UDP	ident—Authentication Service/Identification Protocol, used by IRC servers to identify users	Official
123		UDP	Network Time Protocol (NTP)—used for time synchronization	Official
873	TCP	UDP	rsync file synchronisation protocol	Official USA only
6277		UDP	Distributed Checksum Clearinghouses (anti-spam)	Unofficial

If you’re just starting out, I highly recommend using the Medium pre-configured setting in ConfigServer Security & Firewall. You’ll stop much of the potential pains in being a server administrator while you learn more about adjusting it to your specific needs.

Port details referenced from List of TCP and UDP port numbers on Wikipedia.