title: How to force a mongod to become primary in a replica set?
body: <p>1) I have 3 mongodbs running in a replica set</p>
  
  <pre><code>mongod --fork --logpath a.log --smallfiles --oplogSize 50 --port 27001 --dbpath data/z1 --replSet z
  mongod --fork --logpath b.log --smallfiles --oplogSize 50 --port 27002 --dbpath data/z2 --replSet z
  mongod --fork --logpath c.log --smallfiles --oplogSize 50 --port 27003 --dbpath data/z3 --replSet z
  </code></pre>
  
  <p>2) Now 27001 and 27002 are down.</p>
  
  <p>What do I need to do to make 27003 primary without restarting 27001 and 27002?</p>