Roundcube on Ubuntu 24.04 LTS by cloudimg

Roundcube is the widely used open source browser based IMAP mail client, giving users a fast, full featured webmail experience with folder management, threaded conversations, a rich text composer with attachments and drafts, a searchable address book with contact groups, message search across folders, and a responsive interface that works from desktop to phone. This image is built and maintained by cloudimg on a hardened, fully patched Ubuntu 24.04 LTS base, with Roundcube 1.7 served by nginx and PHP 8.3 FPM and a bundled local MariaDB server holding preferences and contacts. The web installer has already been run and removed, so you land directly on the webmail sign in page.

Roundcube is a mail client rather than a mail store, so a bare Roundcube install has nothing to sign in to. This image therefore also bundles a local Dovecot IMAP server holding a real mailbox and a Postfix mail transfer agent, so the appliance is complete and useful on its own: browse to it on port 80, sign in, and read and compose mail immediately. You can keep the bundled mailbox or point Roundcube at your own corporate IMAP and SMTP servers by changing two settings, as covered in the deployment guide.

A unique mailbox password, a unique database password and a unique encryption key for stored session passwords are generated on the first boot of every VM, and the mailbox password is written to a root only file. The shipped image carries the mailbox credential rotated to a discarded random value, so no known or blank credential authenticates. Dovecot system authentication is disabled, so only the virtual mailbox user can sign in and operating system accounts can never access webmail.

The MariaDB database and the Dovecot mail store both live on a single dedicated managed data disk kept separate from the operating system disk, so your mail data rides with the VM. The bundled MariaDB, Dovecot IMAP and Postfix all listen only on the loopback interface and are never exposed to the network; in particular the mail transfer agent is bound to loopback only and can never act as an open relay. An unauthenticated /healthz endpoint is provided for load balancer probes. For production, front port 80 with your own domain and TLS.

Roundcube is free and open source software licensed under the GNU General Public License version 3, with the upstream exception for skins and plugins. This image is an independent packaging of the open source Roundcube software by cloudimg and is not affiliated with, sponsored by, or endorsed by the Roundcube project. Backed by 24/7 cloudimg support.