zulip-dev start-services will start required services if you don't know which services is causing problems. All the errors are handled by zulip-dev start if you face and error open an issue.

While running ./tools/run-dev.py

The provison will due to script `scripts/setup/configure-rabbitmq`.
or while running `./tools/run-dev.py`
2018-01-28 00:46:09.118 WARN [pika.adapters.base_connection] Connection to 127.0.0.1:5672 failed: [Errno 111] Connection refused
2018-01-28 00:46:09.118 WARN [pika.connection] Could not connect, 0 attempts left
2018-01-28 00:46:09.118 CRIT [zulip.queue] TornadoQueueClient couldn't connect to RabbitMQ, retrying in 2 secs...

Fix: sudo service rabbitmq-server restart

subprocess.CalledProcessError: Command './scripts/setup/flush-memcached' returned non-zero exit status 1

Fix: sudo service memcached start

psycopg2.OperationalError: could not connect to server: Connection refused
        Is the server running on host "0.0.0.0" and accepting
        TCP/IP connections on port 5432?

Fix: sudo service postgresql start

Error 111 connecting to 127.0.0.1:6379. Connection refused. on website when try to login. redis-server is not started, You need start the redis-server

Fix: sudo service redis-server restart

Tornado server is not running on port 9993, in cloud9 case you just changed the base_port and it messup up to tornado_port. To fix this just changed the proxy_port in run-dev.py file and not everything. It recommended to use the zulip-dev start to avoid such errors.

To fix this you have two options:

1. export EXTERNAL_HOST=$C9_HOSTNAME should fix it although you should add it to /srv/zulip-py3-venv/bin/activate so you don't have to run it every time.

2. Edit the zproject/dev_settings.py and add <workspace-name>-<username>.c9users.io to EXTERNAL_HOST and remove the os.environ['EXTERNAL_HOST'].

Nonetheless you can use zulip-dev start avoid doing any of that above.