java doc 针对这个异常的说明
/**
* Signals that an error occurred while attempting to connect a
* socket to a remote address and port. Typically, the remote
* host cannot be reached because of an intervening firewall, or
* if an intermediate router is down.
*/
出现这个问题一般是防火墙默认策略限制导致(如果想看路由信息使用route -n )
这个在linux下是 iptables 在起作用,可以精细的设置多个主机之间的端口访问限制策略,我为了图方便故将这个服务关闭了。
service iptables stop