Sendmail
Sendmail is a widely used open-source mail transfer agent (MTA) for routing and delivering email on Unix and Linux systems. It handles routing emails between mail servers and delivers them to local users' mailboxes.
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Sendmail: Open-Source MTA
A widely used open-source mail transfer agent for routing and delivering email on Unix and Linux systems, handling email routing between servers and local user delivery.
What is Sendmail?
Sendmail is a popular open source email server program (MTA or Mail Transfer Agent) used on Unix/Linux machines to route, deliver, and forward email messages. It is highly configurable and scales well to handle anything from small local email deliveries to enterprise-level bulk email routing.
Some key features of Sendmail include:
- Routing, delivery, and forwarding of email for users on a local system or network
- Flexible configuration using cf and cn build files to handle complex mail routing logic
- Support for SMTP, ESMTP, POP3, IMAP, LDAP, TLS/SSL for security
- Milter interface for integrating spam and virus filtering
- Aliasing, forwarding, automatic BCC, mailing lists
- Scalable design suitable for small office LANs up to huge ISP installs
Sendmail has been around since the early 1980s and established itself as a hugely popular enterprise MTA due to its flexibility and scalability. However, it is also known for being complex and challenging to configure for novices. Most Linux distributions include Sendmail or the compatible Postfix MTA by default for delivering local mail.
Sendmail Features
Features
- Mail Transfer Agent (MTA) for routing and delivering email
- Runs as a daemon on Unix/Linux systems
- Uses SMTP protocol for sending outgoing mail
- Uses a flexible configuration file to control mail routing
- Supports aliases, mailing lists, forwarding, filtering
- Integrates with LDAP directories for authentication
- Includes anti-spam and anti-virus capabilities
Pricing
- Open Source
Pros
Widely used and well established
Open source and free
Highly scalable and reliable
Flexible configuration options
Supports security features like TLS
Integrates with other tools via Milter interface
Cons
Complex configuration syntax
Steep learning curve
Requires expertise to properly secure
Not user friendly administrative interface
Official Links
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