Solving Postfix Newbie Issue: TLS 1.2 Ciphers Get Synology MailPlus Server to Accept SMTP Connection on Lorex DVR

To resolve the issue of TLS connection failure when Lorex DVR sends email notifications using Synology NAS MailPlus Server, it appears that the issue might be related to the TLS 1.2 ciphers. Here's a detailed guide on how to ensure that Synology MailPlus Server accepts SMTP connections from Lorex DVR using TLS 1.2 ciphers.

Prerequisites

Before proceeding, ensure that you have the following:

1. Access to Synology NAS with MailPlus Server installed.
2. Knowledge of Synology DSM (DiskStation Manager) interface.

Steps to configure Synology MailPlus Server

1. Log in to your Synology NAS using a web browser.
2. Navigate to Control Panel > Mail Server.
3. Click on the "SMTP" tab.

Configure SMTP settings

1. Under the "General" settings, enable the "Enable SMTP Service" option.
2. Set the "SMTP Port" to 587 or 465 (depending on your Lorex DVR's requirements).
3. Enable "Start TLS" option.
4. Check the "Allow authenticated users to send email as" option if you want Lorex DVR to send emails as a specific user.

Configure TLS settings

1. Scroll down to the "TLS" settings.
2. Enable the "Use TLS" option.
3. Enable the "Require TLS" option.
4. Select "TLS 1.2" from the "Supported TLS versions" dropdown menu.
5. Ensure the "Cipher Suite" option includes TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256, TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384, and TLS_RSA_WITH_AES_128_GCM_SHA256 ciphers.
6. Save the changes.

Configure Authentication settings

1. Scroll down to the "Authentication" settings.
2. Enable the "Require authentication" option.
3. Set the "Username" and "Password" for the Lorex DVR user.
4. Save the changes.

Test the configuration

1. Restart the MailPlus Server service.
2. Test the configuration by sending a test email from the Lorex DVR.

Summary

In this guide, we've explained how to configure Synology MailPlus Server to accept SMTP connections from Lorex DVR using TLS 1.2 ciphers. This should resolve the TLS connection failure issue when Lorex DVR sends email notifications using Synology NAS MailPlus Server.

References

1. Synology MailPlus Server User Guide: https://www.synology.com/en-global/knowledgebase/DSM/help/Mail/MailPlus/MailPlus_User_Guide
2. Lorex DVR Email Notification Configuration: https://support.lorextechnology.com/hc/en-us/articles/360033551653-Email-Notifications-for-Lorex-DVR-Systems
3. TLS 1.2 Ciphers: https://www.ssllabs.com/ssl-cipher-suite-list.html