How to send emails with Postfix and Amazon AWS SES on RHEL/CentOS 8

To send emails with Postfix and Amazon AWS Simple Email Service (SES) on RHEL/CentOS 8, follow these steps:

1. Install Postfix:

sudo yum install postfix

2. Configure Postfix to use Amazon SES as the SMTP server. Edit the /etc/postfix/main.cf configuration file, and add the following lines at the end:

relayhost = [email-smtp.us-east-1.amazonaws.com]:587
smtp_sasl_auth_enable = yes
smtp_sasl_security_options = noanonymous
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd

3. Create the /etc/postfix/sasl_passwd file, and add the following line to it:

[email-smtp.us-east-1.amazonaws.com]:587 YOUR_AWS_ACCESS_KEY_ID:YOUR_AWS_SECRET_ACCESS_KEY

Replace YOUR_AWS_ACCESS_KEY_ID and YOUR_AWS_SECRET_ACCESS_KEY with your AWS access key ID and secret access key, respectively.

4. Run the following command to create a hashed version of the sasl_passwd file:

sudo postmap /etc/postfix/sasl_passwd

5. Restart Postfix to apply the changes:

sudo systemctl restart postfix

6. Test the configuration by sending an email using the sendmail.