Zimbra OSE: When You Need a Real Mail Server but Don’t Want to Pay for a Brand
Some setups just outgrow simple mail forwarding and webmail panels. Maybe you’re hosting for a mid-sized org, or just tired of patching together Postfix, Dovecot, Roundcube, and a calendar app that kinda works. That’s where Zimbra OSE fits in.
It’s a full-featured collaboration server — email, calendar, contacts, tasks — that runs on your infrastructure and doesn’t come with licensing costs. It’s not light, but it replaces a lot. And once it’s up, it mostly stays up.
What Zimbra OSE Actually Offers
| Component | What It Covers |
| Mail server stack | Postfix, Amavis, SpamAssassin, ClamAV — integrated, preconfigured |
| Webmail frontend | Modern interface with folders, filters, search |
| Calendar and contacts | Built-in groupware — works across devices via CalDAV/CardDAV |
| Mobile sync | Basic support via IMAP/CalDAV, EAS with Z-Push if needed |
| Admin console | Web-based UI for managing domains, quotas, accounts |
| Backup options | Manual, rsync-level, or community tools (no full GUI backup) |
| Multidomain support | Handle multiple orgs on a single server |
| Open standards | IMAP, SMTP, POP3, LDAP, HTTPS — no vendor lock-in |
When It’s a Good Fit
– Want self-hosted, all-in-one groupware
– Need something more robust than Roundcube + dovecot
– Have internal or external users that rely on shared calendars and address books
– Run multi-user mail hosting across domains
– Are okay with some manual sysadmin work in exchange for licensing freedom
It’s not a Gmail clone. But it does give you the core collaboration features without subscriptions, telemetry, or feature gating.
Getting Zimbra OSE Running (Ubuntu Example)
- Use a fresh VM or container — Zimbra wants to own the box. Disable conflicting services like postfix or named.
- Set hostname and DNS (important — Zimbra depends on correct resolution):
hostnamectl set-hostname mail.example.com
- Download Zimbra OSE:
wget https://files.zimbra.com/downloads/8.8.15_GA/zcs-8.8.15_GA_*.tgz
tar xvf zcs-8.8.15_GA_*.tgz
cd zcs-*
./install.sh
Follow the CLI wizard. Choose components (leave out proxy if not needed). After install, access the web interface:
https://mail.example.com:7071
Admin login: admin@example.com
Strengths and What to Watch Out For
What it gets right:
– Fully integrated — no need to stitch together separate tools
– Web UI is decent — usable across mobile and desktop
– LDAP-based — easy to tie into existing user systems
– Long-running, stable releases — patchable and predictable
– Solid community — forums, scripts, and guides available
What to consider:
– Heavy install — not for shared hosting or low-resource VPS
– Upgrades require planning and patience (read changelogs!)
– Mobile sync beyond IMAP needs extra tools (like Z-Push)
– No built-in GUI backups — you’ll script those yourself
– Community edition gets updates slower than Network Edition
Final Thoughts
Zimbra OSE is for teams that want enterprise-grade mail and groupware without the vendor pricing. It’s a “set it up and let it run” kind of tool, and once dialed in, it serves users well. You’ll need to babysit it now and then, but it gives you freedom — and a whole stack — in one place.
