title: Remove oldest commits from git repository
body: <blockquote>
    <p><strong>Possible Duplicate:</strong><br>
    <a href="https://stackoverflow.com/questions/4987341/completely-remove-old-git-commits-from-history">Completely remove (old) git commits from history</a>  </p>
  </blockquote>
  
  
  
  <p>git is very useful for nightly snapshots of client web sites. Knowing everything (php + mysqldump + user file uploads) is in a git repository provides great peace of mind.</p>
  
  <p>Due to the large size of some of the sites, I am wondering if anyone is aware a moderately easy way to remove (for example) all commits older than 30 days?</p>