- From the Admin console Home page, go to AppsG SuiteGmailAdvanced settings.
- Scroll to the SMTP relay service setting in the Routing section, hover over the setting, and click Configure.
- Enter a unique description.
- In the Allowed senders section, select the users who are allowed to send messages through the SMTP relay service:
- Only registered Apps users in my domain—The sender must be a registered user in one of your domains.
- Only addresses in my domains—The sender doesn't have to be a recognized G Suite user, but must be in one of your registered domains. T
- Any addresses (not recommended)—The sender address can be anything, even an address outside of your domain.
- In the Authentication section, check one or both boxes to set an authentication method:
- Only accept mail from the specified IP addresses—The system only accepts mail sent from these IP addresses as coming from your domains.
- Require SMTP Authentication—Enforces the use of SMTP authentication to identify the sending domain. Using this option requires your clients to connect via TLS.
- If you chose to only accept messages from specified IP addresses, enter the IP addresses:
- Click Add IP RANGE.
- Enter a description for the IP address or range.
- Enter the IP address or range.
- Check the Enabled box to enable (or uncheck to disable) this IP address or range.
- Click Save.
- Check the Require TLS encryption box
Note: If your email server does not support TLS, do not check this box. If you check this box, Google rejects messages that are not encrypted.
- Click Add setting or Save.
- At the bottom, click Save.
- Use the following setting to relay emails:
|Port||587 TLS required|
|Port||25, 587 or 465 (TLS not required)|
|NOTE: Without TLS encryption, you will be unable to use SMTP authentication and must use IP address authentication.|