Outgoing email

Zulip needs to be able to send email so it can confirm new users' email addresses and send notifications.

How to configure

1. Identify an outgoing email (SMTP) account where you can have Zulip send mail. If you don't already have one you want to use, see Email services below.

2. Fill out the section of /etc/zulip/settings.py headed "Outgoing email (SMTP) settings". This includes the hostname and typically the port to reach your SMTP provider, and the username to log in to it. You'll also want to fill out the noreply email section.

3. Put the password for the SMTP user account in /etc/zulip/zulip-secrets.conf by setting email_password. For example: email_password = abcd1234.

Like any other change to the Zulip configuration, be sure to restart the server to make your changes take effect.

1. Configure your SMTP server to allows your Zulip server to send emails originating from the email addresses listed in /etc/zulip/settings.py as ZULIP_ADMINISTRATOR, NOREPLY_EMAIL_ADDRESS and if ADD_TOKENS_TO_NOREPLY_ADDRESS=True (the default), TOKENIZED_NOREPLY_EMAIL_ADDRESS.

If you don't know how to do this, we recommend using a free transactional email service; they will guide you through everything you need to do, covering details like configuring DKIM/SPF authentication so your Zulip emails won't be spam filtered.

1. Use Zulip's email configuration test tool, documented in the Troubleshooting section, to verify that your configuration is working.

2. Once your configuration is working, restart the Zulip server with su zulip -c '/home/zulip/deployments/current/scripts/restart-server'.

Email services

Free outgoing email services

For sending outgoing email from your Zulip server, we highly recommend using a "transactional email" service like Mailgun, SendGrid, or, for AWS users, Amazon SES. These services are designed to send email from servers, and are by far the easiest way to get outgoing email working reliably (Mailgun has the best documentation).

If you don't have an existing outgoing SMTP provider, don't worry! Each of the options we recommend above (as well as dozens of other services) have free options. Once you've signed up, you'll want to find the service's provided "SMTP credentials", and configure Zulip as follows:

• The hostname like EMAIL_HOST = 'smtp.mailgun.org' in /etc/zulip/settings.py
• The username like EMAIL_HOST_USER = 'username@example.com' in /etc/zulip/settings.py.
• The TLS setting as EMAIL_USE_TLS = True in /etc/zulip/settings.py, for most providers
• The port as EMAIL_PORT = 587 in /etc/zulip/settings.py, for most providers
• The password like email_password = abcd1234 in /etc/zulip/zulip-secrets.conf.

Using system email

If you'd like to send outgoing email using the local operating system's email delivery configuration (e.g. you have postfix configuration on the system that forwards email sent locally into your corporate email system), you will likely need to use something like these setting values:

EMAIL_HOST = 'localhost'
EMAIL_PORT = 25
EMAIL_USE_TLS = False
EMAIL_HOST_USER = ""

We should emphasize that because modern spam filtering is very aggressive, you should make sure your downstream email system is configured to properly sign outgoing email sent by your Zulip server (or check your spam folder) when using this configuration. See documentation on using Django with a local postfix server for additional advice.

Using Gmail for outgoing email

We don't recommend using an inbox product like Gmail for outgoing email, because Gmail's anti-spam measures make this annoying. But if you want to use a Gmail account to send outgoing email anyway, here's how to make it work: * Create a totally new Gmail account for your Zulip server; you don't want Zulip's automated emails to come from your personal email address. * If you're using 2-factor authentication on the Gmail account, you'll need to use an app-specific password. * If you're not using 2-factor authentication, read this Google support answer and configure that account as "less secure"; Gmail doesn't allow servers to send outgoing email by default. * Note also that the rate limits for Gmail are also quite low (e.g. 100 / day), so it's easy to get rate-limited if your server has significant traffic. For more active servers, we recommend moving to a free account on a transactional email service.

Logging outgoing email to a file for prototyping

For prototyping, you might want to proceed without setting up an email provider. If you want to see the emails Zulip would have sent, you can log them to a file instead.

To do so, add these lines to /etc/zulip/settings.py:

EMAIL_BACKEND = 'django.core.mail.backends.filebased.EmailBackend'
EMAIL_FILE_PATH = '/var/log/zulip/emails'

Then outgoing emails that Zulip would have sent will just be written to files in /var/log/zulip/emails/.

Remember to delete this configuration (and restart the server) if you later set up a real SMTP provider!

Troubleshooting

You can quickly test your outgoing email configuration using:

su zulip -c '/home/zulip/deployments/current/manage.py send_test_email user@example.com'

If it doesn't throw an error, it probably worked; you can confirm by checking your email. You should get two emails: One sent by the default From address for your Zulip server, and one sent by the "noreply" From address.

If it doesn't work, check these common failure causes:

• Your hosting provider may block outgoing SMTP traffic in its default firewall rules. Check whether the port EMAIL_PORT is blocked in your hosting provider's firewall.

• Your SMTP server's permissions might not allow the email account you're using to send email from the noreply email addresses used by Zulip when sending confirmation emails.

For security reasons, Zulip sends confirmation emails (used for account creation, etc.) with randomly generated from addresses starting with noreply-.

If necessary, you can set ADD_TOKENS_TO_NOREPLY_ADDRESS to False in /etc/zulip/settings.py (which will cause these confirmation emails to be sent from a consistent noreply@ address). Disabling ADD_TOKENS_TO_NOREPLY_ADDRESS is generally safe if you are not using Zulip's feature that allows anyone to create an account in your Zulip organization if they have access to an email address in a certain domain. See this article for details on the security issue with helpdesk software that ADD_TOKENS_TO_NOREPLY_ADDRESS helps protect against.

• Make sure you set the password in /etc/zulip/zulip-secrets.conf.

• Check the username and password for typos.

• Be sure to restart your Zulip server after editing either settings.py or zulip-secrets.conf, using /home/zulip/deployments/current/scripts/restart-server . Note that the manage.py command above will read the latest configuration from the config files, even if the server is still running with an old configuration.

Advanced troubleshooting

Here are a few final notes on what to look at when debugging why you aren't receiving emails from Zulip:

• Most transactional email services have an "outgoing email" log where you can inspect the emails that reached the service, whether an email was flagged as spam, etc.

• Starting with Zulip 1.7, Zulip logs an entry in /var/log/zulip/send_email.log whenever it attempts to send an email. The log entry includes whether the request succeeded or failed.

• If attempting to send an email throws an exception, a traceback should be in /var/log/zulip/errors.log, along with any other exceptions Zulip encounters.

• If your SMTP provider uses SSL on port 465 (and not TLS on port 587), you need to set EMAIL_PORT = 465 as well as replacing EMAIL_USE_TLS = True with EMAIL_USE_SSL = True; otherwise, Zulip will try to use the TLS protocol on port 465, which won't work.

• Zulip's email sending configuration is based on the standard Django SMTP backend configuration. So if you're having trouble getting your email provider working, you may want to search for documentation related to using your email provider with Django.

The one thing we've changed from the Django defaults is that we read the email password from the email_password entry in the Zulip secrets file, as part of our policy of not having any secret information in the /etc/zulip/settings.py file. In other words, if Django documentation references setting EMAIL_HOST_PASSWORD, you should instead set email_password in /etc/zulip/zulip-secrets.conf.