Synacor no longer provides free FOSS binaries. Anyone wanting Zimbra 10.1 on Ubuntu downloads the community tarball: maldua/zimbra-foss, builds from bTactic. Below: a clean installation on Ubuntu 22.04 and 24.04 LTS, DNS, install.sh and the first zmcontrol status. This is not an official Synacor build; it is the tarball the forum uses now that OSE is dead.
What Maldua FOSS is
The zimbra-foss packages the same zm-build from Zimbra Collaboration Suite, without the Network Edition modules. The download page is maldua.github.io/zimbra-foss/downloads. The .tgz are published on GitHub Releases. Code license: GPL-2.0. No warranty.
In September 2026 the picture was:
- 10.1.18.p1 — stable (15+ days on the forum without serious complaints)
- 10.1.20.p1 — recent (20 Aug 2026), with Pimbra security patches included
FOSS x.y.z should carry the same patch level as Network x.y.z; Synacor's embargo can delay it by up to two moons. Ubuntu 18.04 still has a tarball — do not use it, LTS has ended. This how-to follows the path of Ubuntu 22.04 or 24.04, a single server, a real FQDN.
The suite's history: The history of the Zimbra server. This blog's old how-to, still on 8.7: Installing Zimbra 8.7.1 on Ubuntu.
Before downloading: DNS or do not even start
The installer resolves the hostname. If hostname -f does not return the FQDN, or the MX points elsewhere, install.sh aborts or the MTA goes silent. In the domain's DNS:
# A
mail.exemplo.com.br. IN A 203.0.113.10
# MX
exemplo.com.br. IN MX 10 mail.exemplo.com.br.
# PTR (no provedor)
10.113.0.203.in-addr.arpa. IN PTR mail.exemplo.com.br.
On the server:
sudo hostnamectl set-hostname mail.exemplo.com.br
# /etc/hosts — IP público (ou o da LAN, se o MX interno for esse)
echo "203.0.113.10 mail.exemplo.com.br mail" | sudo tee -a /etc/hosts
hostname -f # mail.exemplo.com.br
getent hosts mail.exemplo.com.br
host -t mx exemplo.com.br
host mail.exemplo.com.br
Do not install on the same box that already has Postfix, ISPConfig or another MTA. Zimbra brings its own Postfix, LDAP, Jetty, amavis, and ClamAV. Conflicts on ports 25/53/80/443 are the fastest way to lose an afternoon.
Hardware and packages
An honest minimum for a small domain: 4 vCPU, 8 GB of RAM (16 GB with antivirus + search indexing), 50 GB free in / (the data lives in /opt/zimbra). x86_64. No FIPS.
sudo apt update && sudo apt -y full-upgrade
[ -f /var/run/reboot-required ] && sudo reboot
Ubuntu 22.04:
sudo apt -y install wget curl gnupg2 net-tools dnsutils
libidn12 libpcre3 libgmp10 libexpat1 libstdc++6 libaio1
unzip pax sysstat sqlite3 netcat-openbsd
Ubuntu 24.04 — libaio1 became libaio1t64:
sudo apt -y install wget curl gnupg2 net-tools dnsutils
libidn12 libpcre3 libgmp10 libexpat1 libstdc++6 libaio1t64
unzip pax sysstat sqlite3 netcat-openbsd
If Ubuntu came with Postfix from tasksel:
sudo systemctl stop postfix 2>/dev/null || true
sudo systemctl disable postfix 2>/dev/null || true
sudo apt -y remove postfix
Firewall (adjust the source if admin port 7071 should not be internet-accessible):
sudo ufw allow 22,25,80,443,465,587,993,995,7071/tcp
sudo ufw enable
Download the right tarball
Open the download page, choose the row for your Ubuntu version, and copy the 64bit link. The filename changes with each build — the example below is 10.1.20.p1 from 20 Aug 2026. Check the SHA256 in the .sha256 beside the tarball.
Ubuntu 22.04:
cd /usr/src
sudo wget -O zcs.tgz
https://github.com/maldua/zimbra-foss/releases/download/zimbra-foss-build-ubuntu-22.04/10.1.20.p1/zcs-10.1.20_GA_4200001.UBUNTU22_64.20260820122323.tgz
sudo wget -O zcs.tgz.sha256
https://github.com/maldua/zimbra-foss/releases/download/zimbra-foss-build-ubuntu-22.04/10.1.20.p1/zcs-10.1.20_GA_4200001.UBUNTU22_64.20260820122323.tgz.sha256
# o .sha256 cita o nome original; alinhe:
sha256sum zcs.tgz
# esperado 10.1.20.p1 Ubuntu 22.04:
# 48da60421d9e291033680dd0bbdc0f51ce24124ab9687c0018d913d657d736c5
Ubuntu 24.04, same patch:
cd /usr/src
sudo wget -O zcs.tgz
https://github.com/maldua/zimbra-foss/releases/download/zimbra-foss-build-ubuntu-24.04/10.1.20.p1/zcs-10.1.20_GA_4200001.UBUNTU24_64.20260820122254.tgz
# SHA256 esperado:
# 53d025e2bfc855e56364dd2e46cd8aee801a4ac6216d4217a36bc4a050fd6a1e
Conservative production setup: use the Stable row (10.1.18.p1) on the same page. Do not mix a tarball for 22.04 into 24.04 — the UBUNTU22_64 / UBUNTU24_64 in the name is the contract.
sudo tar xzf zcs.tgz
cd zcs-10.1.20_GA_4200001.UBUNTU*_64.*
install.sh
Run as root. Maldua FOSS has no Network license; if the script asks for activation:
sudo ./install.sh --skip-activation-check
Otherwise, sudo ./install.sh. Typical answers for a single box:
- Accept the license:
Y - Use Zimbra's package repository:
N— the official FOSS repository went offline; the.debare already in the tarball - Packages (single server):
- ldap, logger, mta, snmp, store, apache, spell, memcached, proxy —
Y - dnscache — N on Ubuntu (conflicts with
systemd-resolvedon port 53) - legacy imapd — N
- chat/Zulip if it appears — N (it is Network / a separate service)
- ldap, logger, mta, snmp, store, apache, spell, memcached, proxy —
- Modify the system:
Y - Domain:
exemplo.com.br - Admin password: a long password; the user is
admin@exemplo.com.br - Timezone:
America/Sao_Paulo
The interactive menu lets you edit the hostname, LDAP, and proxy ports. If the MX DNS does not match, the installer warns you — fix it and continue, do not ignore it.
At the end:
su - zimbra -c 'zmcontrol status'
ldap, mailbox, mta, proxy, amavis, antivirus, antispam, logger, snmp, spell, stats, zimbra webapp, service webapp — Running. Webmail: https://mail.exemplo.com.br. Admin: https://mail.exemplo.com.br:7071.
First steps
su - zimbra
zmprov ca joao@exemplo.com.br 'SenhaForteAqui'
zmprov ga joao@exemplo.com.br zimbraAccountStatus
zmcontrol restart
exit
The certificate is self-signed. Replace it later with zmcertmgr (commercial or Let’s Encrypt). Ports 80/443 need to reach Zimbra's proxy for HTTP-01.
Minimum backup, still on day 0:
su - zimbra -c '/opt/zimbra/libexec/zmslapcat /opt/zimbra/backup/ldap'
# snapshot da VM antes de qualquer upgrade
Upgrading and what not to do
Upgrade from 8.8.15 / 9 / 10.0 to 10.1: snapshot, zmcontrol stop, the tarball for the same distro, ./install.sh and accept the upgrade. Maldua's README still marks the upgrade guides as TODO — test on a clone. There is a forum report of 20.04→22.04 with the same FOSS, stopping Zimbra, running do-release-upgrade and reinstalling the new Ubuntu tarball over /opt/zimbra.
Do not mix Network and FOSS. Do not point install.sh at Synacor's paid repository. Do not run the RHEL tarball on Ubuntu.
Wrap-up
A clean Ubuntu LTS, FQDN in DNS, Maldua tarball, install.sh without Synacor's repo, dnscache disabled. The orange smile opens in the browser again. For those who prefer lean webmail on the same postfix: Roundcube.
Downloads: maldua.github.io/zimbra-foss/downloads · code: github.com/maldua/zimbra-foss · forum: Maldua’s Zimbra FOSS Builds · Pimbra: maldua-pimbra.