Superlative SMTP from SuSE

SuSE eMail Server III is an open-source e-mail application featuring integrated installation and Web-based configuration. The suite, which now includes SKYRiX Web Groupware for scheduling and Web-based e-mail, supports SMTP, POP3, IMAP4, LDAP, TLS and HTML-based mail access. The product's fast, authenticated SMTP implementation and good anti-spam functionality make it an excellent SMTP server for any enterprise.

Now based on SuSE Linux Enterprise Server 7, eMail Server III replaces the basic IMP Webmail client included with version II with the user-friendly and feature-rich SKYRiX Web mail client, which brings address book and scheduling functionality to the suite. And, in contrast to its predecessor, e-Mail Server III now supports true virtual domains.

SuSE simplifies system setup with its all-encompassing installation/configuration application, YaST2, which can be run from the command line or under the X GUI. As with version II, all e-mail related configuration changes are performed via YaST2's browser-based administration tool.

As a primary mail server, SuSE eMail Server III isn't really suitable for larger companies, as it's limited to a maximum of 1000 mailboxes. Unlike Exchange Server or CommuniGate Pro, eMail Server III is designed as a one-server system with no clustering capabilities. And since the product lacks an online backup facility, finding an appropriate time to take the server offline for backup can be a challenge.

While its utility as an enterprise mail system is limited, eMail Server III is well-suited for use as a bastion host and SMTP server. Many corporations deploy SMTP servers outside a firewall or in a DMZ to check the validity of incoming e-mails and reject spam e-mail before forwarding messages to an internal mail server.

eMail Server III is very well suited for this task because it uses the Postfix MTA (Message Transfer Agent), which is straightforward and relatively simple to configure compared to the complex Sendmail MTA, yet functionally equivalent to Sendmail. Also, eMail Server III supports encrypted, authenticated SMTP through SASL (Simple Authentication and Security Layer). Many MTAs use only SASL's user database, sasldb, to provide unencrypted authentication, because most mail clients don't support the encrypted formats that sasldb provides. eMail Server III overcomes this problem by using mailbox accounts instead of sasldb to authenticate SMTP clients via SASL; by selecting a single checkbox in the configuration application, you can enable support for TLS-based encryption, which mail clients such as Outlook can use to authenticate securely.

SuSE eMail Server III lists at $999, which includes 30 days of support, one year of maintenance (access to all security/bug fixes), and a licensed copy of Knox Software's Arkeia backup application. Enterprises running a previous version of SuSE eMail Server can upgrade to version III for $699. Additionally, eMail Server III includes three well-structured, printed manuals.

Although SuSE eMail Server III's lack of an online backup facility makes it ill-suited as a replacement for Exchange-caliber mail servers, it will function quite well as an SMTP or mail relay server for forwarding e-mail to an e-mail system such as Exchange. Enterprises looking to increase messaging security and reliability and reduce TCO should consider SuSE's low-cost messaging solution.