Requirements

Note that if you just want to play around with Zulip and see what it looks like, it is easier to install it in a development environment following these instructions, since then you don't need to worry about setting up SSL certificates and an authentication mechanism. Or, you can check out the developers' chatroom (a public, running Zulip instance).

Server

Hardware Specifications

• CPU and Memory: For installations with 100+ users you'll need a minimum of 2 CPUs and 4GB RAM. For installations with fewer users, 1 CPU and 2GB RAM is sufficient. We strong recommend against installing with less than 2GB of RAM, as you will likely experience out of memory issues installing dependencies. We recommend against using highly CPU-limited servers like the AWS t2 style instances for organizations with a hundreds of users (active or no).

• Disk space: You'll need at least 10GB of free disk space. If you intend to store uploaded files locally rather than on S3 you will likely need more.

Network and Security Specifications

• Incoming HTTPS access (usually port 443, though this is configurable) from the networks where your users are (usually, the public Internet). If you also open port 80, Zulip will redirect users to HTTPS rather than not working when users type e.g. http://zulip.example.com in their browser. If you are using Zulip's incoming email integration you may also need incoming port 25 open.

• Outgoing HTTP(S) access (ports 80 and 443) to the public Internet so that Zulip can properly manage inline image previews. If you want to be able to send email from Zulip, you'll also need outgoing SMTP access to your mail server (using port 587).

Operating System

Ubuntu 14.04 Trusty and Ubuntu 16.04 Xenial are supported for running Zulip in production. 64-bit is recommended.

Domain name

You should already have a domain name available for your Zulip production instance. In order to generate valid SSL certificates with Let's Encrypt, and to enable other services such as Google Authentication, you'll need to update the domains A record to point to your production server.

Credentials needed

SSL Certificate

• SSL Certificate for the host you're putting this on (e.g. zulip.example.com). The installation instructions contain documentation for how to get an SSL certificate for free using LetsEncrypt.

Outgoing email

• Email credentials Zulip can use to send outgoing emails to users (e.g. email address confirmation emails during the signup process, missed message notifications, password reminders if you're not using SSO, etc.).

Once you have met these requirements, see full instructions for installing Zulip in production.