Mongos alway exit unexpectedly
<p>I started one Mongos server by the following command:</p>

<pre><code>nohup mongos --port 57017 --configdb configsvr1:47017,configsvr2:47017,configsvr3:47017 &gt; s.nohup 2&gt;&amp;1 &amp;
</code></pre>

<p>configsvr* are configuration servers. my problem is that Mongos instance always exit after a few hour.
The Mongos log I found as following:</p>

<pre><code>W SHARDING [LockPinger] Error encountered while stopping ping on mongos_server:
57017:1472436263:-1365656364 :: caused by :: 17382 
Can't use connection pool during shutdown
I SHARDING [signalProcessingThread] dbexit:  rc:0
</code></pre>