# Installation

Ensure you have an Ubuntu system that satisfies [the installation
requirements](prod-requirements.html).  In short, you should have an
Ubuntu 14.04 Trusty or Ubuntu 16.04 Xenial 64-bit server instance,
with at least 4GB RAM, 2 CPUs, and 10 GB disk space.  You should also
have a domain name available and have updated its DNS record to point
to the server.

## Step 0: Subscribe

Please subscribe to low-traffic [the Zulip announcements Google
Group](https://groups.google.com/forum/#!forum/zulip-announce) to get
announcements about new releases, security issues, etc.

## Step 1: Install SSL Certificates

Zulip runs over https only and requires ssl certificates in order to
work. It looks for the certificates in `/etc/ssl/private/zulip.key`
and `/etc/ssl/certs/zulip.combined-chain.crt`.  Note that Zulip uses
`nginx` as its webserver and thus [expects a chained certificate
bundle](http://nginx.org/en/docs/http/configuring_https_servers.html)

If you need an SSL certificate, see [our SSL certificate
documentation](ssl-certificates.html).  If you already have an SSL
certificate, just install (or symlink) them into place at the above
paths, and move on to the next step.

## Step 2: Download and install latest release

If you haven't already, download and unpack [the latest built server
tarball](https://www.zulip.com/dist/releases/zulip-server-latest.tar.gz)
with the following commands:

```
sudo -i  # If not already root
cd /root
wget https://www.zulip.com/dist/releases/zulip-server-latest.tar.gz
rm -rf /root/zulip && mkdir /root/zulip
tar -xf zulip-server-latest.tar.gz --directory=/root/zulip --strip-components=1
```

Then, run the Zulip install script:
```
/root/zulip/scripts/setup/install
```

This may take a while to run, since it will install a large number of
dependencies.

The Zulip install script is designed to be idempotent, so if it fails,
you can just rerun it after correcting the issue that caused it to
fail.  Also note that it automatically logs a transcript to
`/var/log/zulip/install.log`; please include a copy of that file in
any bug reports.

## Step 3: Configure Zulip

Configure the Zulip server instance by editing `/etc/zulip/settings.py` and
providing values for the mandatory settings, which are all found under the
heading `### MANDATORY SETTINGS`.

These settings include:

- `EXTERNAL_HOST`: the user-accessible Zulip domain name for your Zulip
  installation. This will be the domain for which you have DNS A records
  pointing to this server and for which you configured SSL certificates.

- `ZULIP_ADMINISTRATOR`: the email address of the person or team maintaining
  this installation and who will get support emails.

- `AUTHENTICATION_BACKENDS`: a list of enabled authentication
  mechanisms.  You'll need to enable at least one authentication
  mechanism by uncommenting its corresponding line, and then also do
  any additional configuration required for that backend as documented
  in the `settings.py` file.  See the [section on
  Authentication](prod-authentication-methods.html) for more detail on the
  available authentication backends and how to configure them.

- `EMAIL_*`, `DEFAULT_FROM_EMAIL`, and `NOREPLY_EMAIL_ADDRESS`:
  Regardless of which authentication backends you enable, you must
  provide settings for an outgoing SMTP server so Zulip can send
  emails when needed (and don't forget to set `email_password` in
  the `zulip-secrets.conf` file).  We highly recommend testing
  your configuration using `manage.py send_test_email` to confirm
  your outgoing email configuration is working correctly.

- `ALLOWED_HOSTS`: Replace `*` with the fully qualified DNS name for
  your Zulip server here.

## Step 4: Initialize Zulip database

At this point, you are done doing things as root.  To initialize the
Zulip database for your production install, run:

```
su zulip -c /home/zulip/deployments/current/scripts/setup/initialize-database
```

The `initialize-database` script will report an error if you did not
fill in all the mandatory settings from `/etc/zulip/settings.py`.  It
is safe to rerun it after correcting the problem if that happens.

This completes the process of installing Zulip on your server.
However, in order to use Zulip, you'll need to create an organization
in your Zulip installation.

## Step 5: Create a Zulip organization and login

* If you haven't already, verify that your server can send email using
`./manage.py send_test_email username@example.com`.  You'll need
working outgoing email to complete the setup process.

* Run the organization (realm) creation [management
command](prod-maintain-secure-upgrade.html#management-commands) :

  ```
  su zulip # If you weren't already the zulip user
  cd /home/zulip/deployments/current
  ./manage.py generate_realm_creation_link
  ```

  This will print out a secure 1-time use link that allows creation of a
  new Zulip organization on your server.  For most servers, you will
  only ever do this once, but you can run `manage.py
  generate_realm_creation_link` again if you want to host another
  organization on your Zulip server.

* Open the link generated with your web browser. You'll see the create
organization page ([screenshot here](_static/zulip-create-realm.png)).
Enter your email address and click *Create organization*.

* Check your email to find the confirmation email and click the
link. You'll be prompted to finish setting up your organization and
initial administrator user ([screenshot
here](_static/zulip-create-user-and-org.png)).  Complete this form and
log in!

**Congratulations!** You are logged in as an organization
administrator for your new Zulip organization.  After getting
oriented, we recommend visiting the special "Administration" tab
linked to from the upper-right gear menu in the Zulip app to configure
important policy settings like how users can join your new
organization. By default, your organization will be configured as
follows depending on what type of organization you selected:

Community Organization:
* `restricted_to_domain=False`: No restriction on user email addresses.
* `invite_required=True`: A user must be invited to join.

Corporate Organization:
* `restricted_to_domain=True`: New users must have an email address in the same domain (e.g. @acme.com) as yours.
* `invite_required=False`: No invitation is required to join.

Next, you'll likely want to do one of the following:

* [Customize your Zulip organization](prod-customize.html).
* [Learn about managing a production Zulip server](prod-maintain-secure-upgrade.html).

## Troubleshooting

If you get an error after `scripts/setup/install` completes, check
`/var/log/zulip/errors.log` for a traceback, and consult the
[troubleshooting section](prod-troubleshooting.html) for advice on
how to debug.  If that doesn't help, please visit [the "installation
help" stream in the Zulip developers'
chat](https://zulip.tabbott.net/#narrow/stream/installation.20help)
for realtime help or email zulip-help@googlegroups.com with the
traceback and we'll try to help you out!