java.net.NoRouteToHostException: No route to host: no further information

之前一直不知道这个错误是怎么回事，今天终于在一次意外中找寻到答案

错误：

16:12:38,921 [ERROR] - ++++ failed to get SockIO obj for: 192.168.1.4:11211
16:12:38,921 [ERROR] - No route to host: no further information
java.net.NoRouteToHostException: No route to host: no further information
at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:574
)
at sun.nio.ch.SocketAdaptor.connect(SocketAdaptor.java:100)
at com.danga.MemCached.SockIOPool$SockIO.getSocket(SockIOPool.java:1612)

at com.danga.MemCached.SockIOPool$SockIO.<init>(SockIOPool.java:1585)
at com.danga.MemCached.SockIOPool.createSocket(SockIOPool.java:782)
at com.danga.MemCached.SockIOPool.selfMaint(SockIOPool.java:1331)
at com.danga.MemCached.SockIOPool$MaintThread.run(SockIOPool.java:1497)
16:12:38,921 [ERROR] - ++++ failed to close socket: ++++ socket or its streams a
lready null in trueClose call
16:12:38,921 [ERROR] - ++++ failed to close SockIO obj from deadPool
16:12:38,921 [ERROR] - ++++ socket or its streams already null in trueClose call

java.io.IOException: ++++ socket or its streams already null in trueClose call
at com.danga.MemCached.SockIOPool$SockIO.trueClose(SockIOPool.java:1704)

at com.danga.MemCached.SockIOPool.selfMaint(SockIOPool.java:1432)
at com.danga.MemCached.SockIOPool$MaintThread.run(SockIOPool.java:1497)
16:12:38,937 [ERROR] - ++++ failed to close SockIO obj from deadPool
16:12:38,937 [ERROR] - ++++ socket or its streams already null in trueClose call

java.io.IOException: ++++ socket or its streams already null in trueClose call
at com.danga.MemCached.SockIOPool$SockIO.trueClose(SockIOPool.java:1704)

at com.danga.MemCached.SockIOPool.selfMaint(SockIOPool.java:1432)
at com.danga.MemCached.SockIOPool$MaintThread.run(SockIOPool.java:1497)
16:12:38,937 [ERROR] - ++++ failed to close SockIO obj from deadPool
16:12:38,937 [ERROR] - ++++ socket or its streams already null in trueClose call

后来经过查询，说是 防火墙设置可能阻挡此类程序访问网络

但觉得不可能，之前运行还是好好的，如果一开始防火墙就阻止是不可能的。

后来想起原来下午不小心让网络断了，于是就想：貌似是断网引起的，结果一测，果真如些。。。