I&#39;m using:

 - Python 3.4.2
 - PyMongo 3.0.2
 - mongolab running mongod 2.6.9
 - uWSGI 2.0.10
 - CherryPy 3.7.0
 - nginx 1.6.2

uWSGI start params:

    --socket 127.0.0.1:8081 --daemonize --enable-threads --threads 2 --processes 2

I setup my MongoClient ONE time:

    self.mongo_client = MongoClient(&#39;mongodb://user:pw@host.mongolab.com:port/mydb&#39;)
    self.db = self.mongo_client[&#39;mydb&#39;]

I try and save a JSON dict to MongoDB:

    result = self.db.jobs.insert_one(job_dict)

It works via a unit test that executes the same code path to mongodb.  However when I execute via CherryPy and uWSGI using an HTTP POST, I get this:

&lt;!-- language: lang-none --&gt;

    pymongo.errors.ServerSelectionTimeoutError: No servers found yet

Why am I seeing this behavior when run via CherryPy and uWSGI?  Is this perhaps the new thread model in PyMongo 3?

**Update:**
 
If I run without uWSGI and nginx by using the CherryPy built-in server, the `insert_one()` works.

**Update 1/25 4:53pm EST:**

After adding some debug in PyMongo, it appears that `topology._update_servers()` knows that the server_type = 2 for server &#39;myserver-a.mongolab.com&#39;.  However `server_description.known_servers()` has the server_type = 0 for server &#39;myserver.mongolab.com&#39;

This leads to the following stack trace:

    result = self.db.jobs.insert_one(job_dict)
    File &quot;/usr/local/lib/python3.4/site-packages/pymongo/collection.py&quot;, line 466, in insert_one
    with self._socket_for_writes() as sock_info:
    File &quot;/usr/local/lib/python3.4/contextlib.py&quot;, line 59, in __enter__
    return next(self.gen)
    File &quot;/usr/local/lib/python3.4/site-packages/pymongo/mongo_client.py&quot;, line 663, in _get_socket
    server = self._get_topology().select_server(selector)
    File &quot;/usr/local/lib/python3.4/site-packages/pymongo/topology.py&quot;, line 121, in select_server
    address))
    File &quot;/usr/local/lib/python3.4/site-packages/pymongo/topology.py&quot;, line 97, in select_servers
    self._error_message(selector))
    pymongo.errors.ServerSelectionTimeoutError: No servers found yet

All Mlab Solutions on Gang of Coders

Total of 1 Mlab Solutions

Why is PyMongo 3 giving ServerSelectionTimeoutError?