The following table lists commonly used ECS instance ports.
|21||FTP||A port opened by the FTP service is used for uploading and downloading files.|
|22||SSH||An SSH port is used to connect to a Linux instance by using a password in command-line mode.|
|23||Telnet||The Telnet port is used for Telnet to log on to the ECS instance.|
|25||SMTP||The port that is open to the SMTP service is used for sending mails.
Based on security concerns, ECS instance Port 25 is restricted by default. Open a ticket to open it. See apply to open TCP port 25.
|80||HTTP||Provides access to HTTP services, such as IIS, Apache, and Nginx.
You can verify if TCP port 80 works properly for port troubleshooting.
|110||POP3||Used for the POP3 protocol, which is the protocol for sending and receiving emails.|
|143||IMAP||Used for IMAP (Internet Message Access Protocol), which is the protocol for receiving emails.|
|443||HTTPS||Used to provide access to the HTTPS service. HTTPS is a protocol that provides encryption and transmission through secure ports.|
|1433||SQL Server||The TCP port of the SQL Server is used for external service by SQL Server.|
|1434||SQL Server||SQL Server UDP port is used to return which TCP/IP port SQL Server uses.|
|1521||Oracle||Oracle communications port. The port which needs to be released by Oracle SQL is deployed on the ECS instance.|
|3306||MySQL||The port through which the MySQL database provides external service.|
|3389||Windows Server Remote Desktop Services||Windows Server Remote Desktop Services port can be used to connect to a Windows instance.|
|8080||Proxy port||As with 80 port, port 8080 is commonly used in WWW agent service to achieve web browsing. If you are using port 8080, when you visit a Web site or use a proxy server, you must add
|137, 138, 139||NetBIOS protocol||
Some ports cannot be accessed
Problem: The ECS instance listens for the corresponding port, but the port is not accessible in some areas, while other ports can be accessed normally.
Analysis: Some operators judge ports 135, 139, 444, 445, 5800, 5900, and so on as high-risk ports, so they are blocked by default.
Solution: We recommend that you change the port to other non-high-risk ports for business operation.
For more information on how to release a service port through a security group, see add security group rules.