1 <?php
 2 function getMongoClient($seeds = "", $options = array(), $retry = 3) {
 3     try {
 4         return new MongoClient($seeds, $options);
 5     } catch(Exception $e) {
 6         /* Log the exception so we can look into why mongod failed later */
 7         logException($e);
 8     }
 9
 
     if ($retry > 0) {
10         return getMongoClient($seeds, $options, --$retry);
11     }
12     throw new Exception("I‘ve tried several times getting MongoClient.. Is mongod really running?");
13 }
14  
15 try {
16     $mc = getMongoClient("localhost", array());
17 } catch(Exception $e) {
18     /*
 
 Can‘t connect to MongoDB! */
19     logException($e);
20     die("Can‘t do anything :(");
21 }

解決方法；失敗重試

mongodb: Remote server has closed the connection