SSL/TLS in Postfix and Dovecot: why and how
Let's Encrypt certificate, ports 465/587/993/995, TLS 1.2 where there is a password, Dovecot 2.3 and 2.4, tests, and MTA-STS against the attack that strips STARTTLS.
Let's Encrypt certificate, ports 465/587/993/995, TLS 1.2 where there is a password, Dovecot 2.3 and 2.4, tests, and MTA-STS against the attack that strips STARTTLS.
SPF, DKIM signing with OpenDKIM, DMARC policy, and verification with OpenDMARC on Postfix, tested on Ubuntu 24.04 and 26.04.
Anyone who has built an email server with Postfix + Dovecot knows the ritual: the classic PHP PostfixAdmin, a web server configured just for it, and an interface frozen in time. go-postfixadmin is my modern answer: a single Go binary with the entire Vue 3 frontend embedded — a dashboard … Read more
Zimbra is the Ajax groupware platform that wanted to be Exchange for Linux. It began as LiquidSys in 2003, became Zimbra Inc. on July 26, 2005, and took its name from the Talking Heads song I Zimbra. In September 2007, Yahoo bought it for US$ 350 million. Then came VMware, Telligent, and Synacor. On the 31 … Read more
In 2002, Mischa Peters of High5! released a PHP application so he would not have to edit MySQL by hand: virtual domains, mailboxes, and aliases. He called it PostfixAdmin. GPL. Postfix delivered the mail; it lacked a service counter. Twenty-four years later, PostfixAdmin 4.0.5 (July 5, 2026) is still that counter — now with TOTP, app passwords, DKIM, … Read more
In July 2002, a Finnish developer who had already written irssi released an IMAP server designed to be neither Courier nor UW. He called it Dovecot — a shelter for pigeons. Five years later, on April 13, 2007, version 1.0.0 arrived. Timo Sirainen noted: “almost five years, but it is ready.” Twenty-four … Read more
In 1997, Wietse Venema at the IBM Thomas J. Watson Research Center began writing an MTA so he would not have to live with Sendmail. On December 14, 1998, the code was released. It was called VMailer, then IBM Secure Mailer, then Postfix — “post” for mail, “fix” for repair. Twenty-eight years later, Postfix … Read more
Zimbra remains the groupware platform closest to an Exchange running on Linux: email, shared calendars, contacts, tasks, and webmail in the same appliance. And it remains heavy — Java, two HTTP servers, and a stack of processes … Read more