PHP logical error in if block

Hey folks the following code consistently hits the else clause, and I'm not understanding why. The Dump is operating just -fine-.  Can anyone help me find a way to troubleshoot as to why it's going to the else block? It should read true in the if().

if($mysqlDump->backup()) {
      $success = array('success' => '1');
      echo  '(' . json_encode($success) . ')';  
} else {
      $fail = array('fail' => '1');
      echo '(' . json_encode($fail) . ')';
}  

My mysqlDump class looks like this:

class MySQLDump {
      private $cmd;
      
      public function __construct($dbUser, $dbPass, $dbName, $dest, $zip='bz2') {
            $zip_util = array('gz' => 'gzip', 'bz2' => 'bzip2' );
            if (array_key_exists($zip, $zip_util)) {
                  $fname = $dbName . '.' . date("w") . '.sql.' . $zip;
                  $this->cmd = 'mysqldump -Q -u' . $dbUser . ' -p' . $dbPass . ' ' . $dbName . '| ' . $zip_util[$zip]
                        . ' >' . $dest . '/' . $fname;
            } else {
                  $fname = $dbName . '.' . date("w") . '.sql.' . $zip;
                  $this->cmd = 'mysqldump -Q -u' . $dbUser . ' -p' . $dbPass . ' ' . $dbName . '| ' . bzip2
                        . ' >' . $dest . '/' . $fname;
            }
      }
      
      public function backup() {
            system($this->cmd, $error);
            if($error) {
                  trigger_error('Snapshot failed: ' . $error);
            }
      }
}   Start Free Trial