Troubleshooting

Zulip uses Supervisor to monitor and control its many Python services. Read the next section, Using supervisorctl, to learn how to use the Supervisor client to monitor and manage services.

If you haven't already, now might be a good time to read Zulip's architectural overview, particularly the Components section. This will help you understand the many services Zulip uses.

If you encounter issues while running Zulip, take a look at Zulip's logs, which are located in /var/log/zulip/. That directory contains one log file for each service, plus errors.log (has all errors), server.log (has logs from the Django and Tornado servers), and workers.log (has combined logs from the queue workers).

The section troubleshooting services on this page includes details about how to fix common issues with Zulip services.

If you run into additional problems, please report them so that we can update this page! The Zulip installation scripts logs its full output to /var/log/zulip/install.log, so please include the context for any tracebacks from that log.

Using supervisorctl

To see what Zulip-related services are configured to use Supervisor, look at /etc/supervisor/conf.d/zulip.conf and /etc/supervisor/conf.d/zulip-db.conf.

Use the supervisor client supervisorctl to list the status of, stop, start, and restart various services.

Checking status with supervisorctl status

You can check if the zulip application is running using:

supervisorctl status

When everything is running as expected, you will see something like this:

process-fts-updates                                             RUNNING   pid 2194, uptime 1:13:11
zulip-django                                                    RUNNING   pid 2192, uptime 1:13:11
zulip-senders:zulip-events-message_sender-0                     RUNNING   pid 2209, uptime 1:13:11
zulip-senders:zulip-events-message_sender-1                     RUNNING   pid 2210, uptime 1:13:11
zulip-senders:zulip-events-message_sender-2                     RUNNING   pid 2211, uptime 1:13:11
zulip-senders:zulip-events-message_sender-3                     RUNNING   pid 2212, uptime 1:13:11
zulip-senders:zulip-events-message_sender-4                     RUNNING   pid 2208, uptime 1:13:11
zulip-tornado                                                   RUNNING   pid 2193, uptime 1:13:11
zulip-workers:zulip-deliver-enqueued-emails                     STARTING
zulip-workers:zulip-events-confirmation-emails                  RUNNING   pid 2199, uptime 1:13:11
zulip-workers:zulip-events-digest_emails                        RUNNING   pid 2205, uptime 1:13:11
zulip-workers:zulip-events-email_mirror                         RUNNING   pid 2203, uptime 1:13:11
zulip-workers:zulip-events-error_reports                        RUNNING   pid 2200, uptime 1:13:11
zulip-workers:zulip-events-feedback_messages                    RUNNING   pid 2207, uptime 1:13:11
zulip-workers:zulip-events-missedmessage_mobile_notifications   RUNNING   pid 2204, uptime 1:13:11
zulip-workers:zulip-events-missedmessage_reminders              RUNNING   pid 2206, uptime 1:13:11
zulip-workers:zulip-events-signups                              RUNNING   pid 2198, uptime 1:13:11
zulip-workers:zulip-events-slowqueries                          RUNNING   pid 2202, uptime 1:13:11
zulip-workers:zulip-events-user-activity                        RUNNING   pid 2197, uptime 1:13:11
zulip-workers:zulip-events-user-activity-interval               RUNNING   pid 2196, uptime 1:13:11
zulip-workers:zulip-events-user-presence                        RUNNING   pid 2195, uptime 1:13:11

Restarting services with supervisorctl restart all

After you change configuration in /etc/zulip/settings.py or fix a misconfiguration, you will often want to restart the Zulip application. You can restart Zulip using:

supervisorctl restart all

Stopping services with supervisorctl stop all

Similarly, you can stop Zulip using:

supervisorctl stop all

Troubleshooting services

The Zulip application uses several major open source services to store and cache data, queue messages, and otherwise support the Zulip application:

  • postgresql
  • rabbitmq-server
  • nginx
  • redis
  • memcached

If one of these services is not installed or functioning correctly, Zulip will not work. Below we detail some common configuration problems and how to resolve them:

  • An AMQPConnectionError traceback or error running rabbitmqctl usually means that RabbitMQ is not running; to fix this, try:

    service rabbitmq-server restart
    

    If RabbitMQ fails to start, the problem is often that you are using a virtual machine with broken DNS configuration; you can often correct this by configuring /etc/hosts properly.

  • If your browser reports no webserver is running, that is likely because nginx is not configured properly and thus failed to start. nginx will fail to start if you configured SSL incorrectly or did not provide SSL certificates. To fix this, configure them properly and then run:

    service nginx restart
    
  • If your host is being port scanned by unauthorized users, you may see messages in /var/log/zulip/server.log like

    2017-02-22 14:11:33,537 ERROR Invalid HTTP_HOST header: '10.2.3.4'. You may need to add u'10.2.3.4' to ALLOWED_HOSTS.
    

    Django uses the hostnames configured in ALLOWED_HOSTS to identify legitimate requests and block others. When an incoming request does not have the correct HTTP Host header, Django rejects it and logs the attempt. For more on this issue, see the Django release notes on Host header poisoning

Next: Making your Zulip instance awesome.