SMTP Configuration Guide for Bitwarden Self-Hosted Servers

This guide provides detailed instructions for setting up and configuring SMTP (Simple Mail Transfer Protocol) for Bitwarden self-hosted servers. It outlines the necessary configurations, emphasizing the importance of using port 587 for email submission, which is the industry standard and supports TLS encryption. The document specifies that port 25 should be avoided for application-level email submission due to its limitations and common blocking by ISPs. It also includes best practices for security configurations, such as enabling TLS encryption and ensuring valid SSL/TLS certificates are used in production environments. The guide further details the steps for validating server certificates and includes example configurations for Microsoft Office 365. Additionally, it highlights the need for testing SMTP connectivity and monitoring email-related logs to catch potential issues early. Overall, the document serves as a comprehensive resource for administrators to effectively manage SMTP settings within Bitwarden deployments.