title: MongoDB data disappeared
body: <p>I have MongoDB running in replication mode, with 3 instances, on AWS. The setup has been up and running for over a year. With periodic updates to the application server (running Node.js code). The application server has been running the same code for several months. Last night all calls to the DB started failing, when I logged in to the AWS EC2 Instance running the  primary MongoDB, I could not find any of the collections from the mongo shell. This is the same mongo shell that's been up and running for months (I use tmux to connect). </p>
  
  <p>Based on the size consumption on the filesystem, from what I remember, I think the data is there, but I'm not sure how to access it now. </p>
  
  <pre><code>sudo /usr/bin/mongod --replSet ReplicaSet --port 27017 --dbpath /data/db
  </code></pre>
  
  <p>The above command was used to start the mongo db, nothing has been changed, but the data simply disappeared last night. The same is true on all 3 servers (Primary and 2 Secondaries)</p>
  
  <p>Any help is extremely welcomed...</p>