diff --git a/src/python/devtest/os/CmdTestOs.py b/src/python/devtest/os/CmdTestOs.py
index dbcf7c6..97ca843 100644
--- a/src/python/devtest/os/CmdTestOs.py
+++ b/src/python/devtest/os/CmdTestOs.py
@@ -94,7 +94,9 @@ class CmdTestOs(MachineCmd): # export
             machine = await Machine.create(env)
             case_filter = None if not env.args.cases else env.args.cases.split(',')
             test_cases = TestCases(env.args.test_case_path, include=case_filter, dummies=env.args.dummy_tests)
-            for phase in TestPhases.Phase:
+            phases = TestPhases.parse(env.args.phases)
+            slog(INFO, "Running phases: {}".format(', '.join([p.name for p in phases])))
+            for phase in phases:
                 if not machine.clear_for_tests():
                     raise Exception("machine is not clear for running tests")
                 delim = '-' * 60 + " Phase {} -- ".format(phase.name)
@@ -118,8 +120,9 @@ class CmdTestOs(MachineCmd): # export
             raise
         finally:
             if machine is not None:
-                await machine.request_shutdown(env)
-                await machine.wait_poweroff(env)
+                if TestPhases.Phase.Shutdown in phases:
+                    await machine.request_shutdown(env)
+                    await machine.wait_poweroff(env)
                 await machine.cleanup(env)
                 for conn in env.connections:
                     if conn.instance:
@@ -136,6 +139,7 @@ class CmdTestOs(MachineCmd): # export
 
     def add_parser(self, parsers):
         p = super().add_parser(parsers)
-        p.add_argument(      "--cases", help="List of dedicated test cases to run, wildcards are supported", default='')
+        p.add_argument("--cases", help="List of dedicated test cases to run, wildcards are supported", default='')
+        p.add_argument("--phases", help="List of phases the test should pass", default='all')
         self.__results.add_arguments(p)
         return p