I am running Jenkins 1.613.

i see the slaves log:
四月 15, 2015 10:15:02 上午 com.youdevise.hudson.slavestatus.SlaveListener call
信息: Slave-status listener starting
四月 15, 2015 10:15:02 上午 com.youdevise.hudson.slavestatus.SocketHTTPListener waitForConnection
信息: Slave-status listener ready on port 3141
四月 15, 2015 1:41:01 下午 hudson.remoting.jnlp.Main createEngine
信息: Setting up slave: 192.168.161.8
四月 15, 2015 1:41:01 下午 hudson.remoting.jnlp.Main$CuiListener <init>
信息: Jenkins agent is running in headless mode.
四月 15, 2015 1:41:01 下午 hudson.remoting.jnlp.Main$CuiListener status
信息: Locating server among http://192.168.95.37:8080/jenkins/
四月 15, 2015 1:41:01 下午 hudson.remoting.jnlp.Main$CuiListener status
信息: Connecting to 192.168.95.37:19994
四月 15, 2015 1:41:01 下午 hudson.remoting.jnlp.Main$CuiListener status
信息: Handshaking
四月 15, 2015 1:41:01 下午 hudson.remoting.jnlp.Main$CuiListener error
严重: The server rejected the connection: 192.168.161.8 is already connected to this master. Rejecting this connection.
java.lang.Exception: The server rejected the connection: 192.168.161.8 is already connected to this master. Rejecting this connection.
at hudson.remoting.Engine.onConnectionRejected(Engine.java:306)
at hudson.remoting.Engine.run(Engine.java:276)