What Should I Do If Emails Configured on an ECS Cannot Be Sent?
- For the emails sent using the browser:
If you use a browser to send emails, enable port 80 for TCP in the outbound direction.
- On the page providing details about the target ECS, find the security group and click the security group ID.
- On the Security Group page, click the Outbound tab and then Add Rule.
- In the dialog box that is displayed, set Protocol/Application to TCP and Port to 80. Then, click OK.Figure 1 Adding port 80
- For the emails sent and received through an email client:
Protocol used on the transmitting end:
SMTPS is used, and the port number is 465. Alternatively, SMTP is used, and the port number is 25.
Port 465 is recommended. If port 25 is required, enable it. For details, see Related Operations (Requesting for Permitting TCP Port 25 for Outbound Transmission).
Protocol used on the receiving end: POP3 is used, and the port number is 110.
Add an inbound rule with Protocol set to TCP and Port to 110. Add an outbound rule with Protocol set to TCP and Port to 465 or 25.
Related Operations (Requesting for Permitting TCP Port 25 for Outbound Transmission)
TCP port 25 is prohibited by default in the outbound direction for security purposes. This configuration affects your service running only if your email service is deployed on the cloud.
Before sending the application, you must agree and guarantee that TCP port 25 is only used to connect to third-party Simple Mail Transfer Protocol (SMTP) servers and that emails are sent using the third-party SMTP servers. If you use the EIP specified in the service ticket to directly send emails over SMTP, we will permanently disable TCP port 25 and you will no longer be able to use it or request for it to be enabled.
- On the Create Service Ticket page, choose Products > Elastic Cloud Server.
For details about how to submit a service ticket, see Submitting a Service Ticket.
- Click Open Port 25 under Select Subtype and click Create Service Ticket.Figure 2 Creating a service ticket
- On the displayed page, enter the required information.