Hi Vishveswara, If you look at the behavior of ServerSocket, or any BSD-like listening server socket in general, there is something called 'backlog'. http://download.oracle.com/javase/1.4.2/docs/api/java/net/ServerSocket.html
In short, backlog is something like a queue, if all your worker thread occupied, the listening server socket is allowed to hold and queue n number of connecting socket. Only when the all threads occupied and backlog full then you will get "connection refused". The connection socket in the backlog is silently accepted but not served yet. If the connection socket was held in the backlog for quite some time (e.g. due to existing worker threads still busy), until it is time out for the connection client socket, then that what you have said may occur: the Tomcat is up and running, yet the connection client socket java.net.ConnectException: Connection timeout: connect. So, what you can detect by a connection client socket is not "whether Tomcat is up and running", instead "whether Tomcat is up and running and able to accept and process one more client socket within the client time out interval". There are cases where "Tomcat is up and running" but "is not able to accept and process one more client socket within the client time out interval" (which is the case when "java.net.ConnectException: Connection timeout: connect" happens). There is an "acceptCount" attribute in server.xml <Connector /> which specifies the backlog. If you set this to 0, it may behave the way you want, but you have to test yourself whether that will be good for the system behaviour and performance from the user point of view. --- daniel baktiar On Thu, Sep 22, 2011 at 18:30, vishveswara chary varanasi < vvchary.varan...@gmail.com> wrote: > Tomcat community has a wiki which providded the > > http://wiki.apache.org/tomcat/HowTo#How_do_I_check_whether_Tomcat_is_UP_or_DOWN.3F_There_is_no_status_command > > i have tried to connect to tomcat using sockect connection on the port > where the tomcat running > > Socket socket = new Socket("hostname", port); > > this works some time and some time even if the tomcat is up and > runnning this is throwing the java.net.ConnectException: Connection > timed out: connect. > > please help me how i can test that whether tomcat is up and running on > a remote machine from a client machine. > > Thanks > > --------------------------------------------------------------------- > To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org > For additional commands, e-mail: users-h...@tomcat.apache.org > >
