从相同的Windows服务重新启动Windows服务

Question

I am trying to restart a windows service from the same windows service with this code:

            var psi = new ProcessStartInfo("net.exe", "stop " + serviceName);
            psi.WindowStyle = ProcessWindowStyle.Hidden;
            psi.UseShellExecute = true;
            psi.WorkingDirectory = Environment.SystemDirectory;
            var st = Process.Start(psi);
            st.WaitForExit();

            psi = new ProcessStartInfo("net.exe", "start " + serviceName);
            psi.UseShellExecute = true;
            psi.WindowStyle = ProcessWindowStyle.Hidden;
            psi.WorkingDirectory = Environment.SystemDirectory;
            st = Process.Start(psi);
            st.WaitForExit();

It is not working but is this even possible from the same service?

If it is possible then can anyone suggest why this does not work?

Answer 1

It doesn't work because once you reach the middle, execution stops in since both parent and child process exit:

/* Running */            var psi = new ProcessStartInfo("net.exe", "stop " + serviceName);
/* Running */            psi.WindowStyle = ProcessWindowStyle.Hidden;
/* Running */            psi.UseShellExecute = true;
/* Running */            psi.WorkingDirectory = Environment.SystemDirectory;
/* st stops svc */       var st = Process.Start(psi);
/* both exit */          st.WaitForExit();

/* never reached */      psi = new ProcessStartInfo("net.exe", "start " + serviceName);
/* never reached */      psi.UseShellExecute = true;
/* never reached */      psi.WindowStyle = ProcessWindowStyle.Hidden;
/* never reached */      psi.WorkingDirectory = Environment.SystemDirectory;
/* never reached */      st = Process.Start(psi);
/* never reached */      st.WaitForExit();

Configure the service in windows to restart itself on failure and then do an unclean exit as @StevieB suggested.

Configure the service to restart itself with a 1000 ms delay on failure:

sc failure serviceName reset= 60 actions= restart/1000

Answer 2

I don't believe there's a clean way of doing this. Once you stop the service, the process is no longer there to start it.

One slightly dirty solution: You could configure the service to restart on error (eg at installation/registration time).

Then when you want to restart programmatically have your service exit with an error eg by calling:

Environment.Exit(-1)

or

Environment.FailFast("Service stopped because...")

Note: If there is a cleaner way of doing this programmatically the account the service is running under would require permissions to be able to restart the service.

Answer 3

You have a deadlock. net is waiting for your service to end, and you are using st.WaitForExit() to wait for net to end.

Eventually net gives up waiting and closes. Then you call net again. But your service never exited in the first place, so the second net invocation sees the service is already started and does nothing.

Finally you return the the main service event loop and see the stop request, and your service exits.

You should be able to write a batch file with the above commands, invoke it, and return to the event loop. Then the first net will wait until the service stops, and the second net will start it again.