Should fix ProcessLookupError exceptions.

gns3server/modules/vpcs/vpcs_vm.py

@@ -245,9 +245,9 @@ class VPCSVM(BaseVM):
             try:
                 yield from asyncio.wait_for(self._process.wait(), timeout=3)
             except asyncio.TimeoutError:
-                self._process.kill()
                 if self._process.returncode is None:
-                    log.warn("VPCS process {} is still running".format(self._process.pid))
+                    log.warn("VPCS process {} is still running... killing it".format(self._process.pid))
+                    self._process.kill()
 
         self._process = None
         self._started = False