[cli][ray] ray start should error by default if there's already an instance running (#10826)

python/ray/tests/conftest.py

@@ -178,9 +178,8 @@ def ray_start_object_store_memory(request):
 @pytest.fixture
 def call_ray_start(request):
     parameter = getattr(
-        request, "param",
-        "ray start --head --num-cpus=1 --min-worker-port=0 --max-worker-port=0"
-    )
+        request, "param", "ray start --head --num-cpus=1 --min-worker-port=0 "
+        "--max-worker-port=0 --port 0")
     command_args = parameter.split(" ")
     out = ray.utils.decode(
         subprocess.check_output(command_args, stderr=subprocess.STDOUT))

python/ray/tests/test_cli.py

@@ -158,9 +158,9 @@ DEFAULT_TEST_CONFIG_PATH = str(
     reason=("Mac builds don't provide proper locale support"))
 def test_ray_start(configure_lang):
     runner = CliRunner()
-    result = runner.invoke(
-        scripts.start,
-        ["--head", "--log-style=pretty", "--log-color", "False"])
+    result = runner.invoke(scripts.start, [
+        "--head", "--log-style=pretty", "--log-color", "False", "--port", "0"
+    ])
     _die_on_error(runner.invoke(scripts.stop))
 
     _check_output_via_pattern("test_ray_start.txt", result)

python/ray/tests/test_multi_node.py

@@ -301,7 +301,7 @@ ray.get([a.log.remote(), f.remote()])
 @pytest.mark.parametrize(
     "call_ray_start", [
         "ray start --head --num-cpus=1 --num-gpus=1 " +
-        "--min-worker-port=0 --max-worker-port=0"
+        "--min-worker-port=0 --max-worker-port=0 --port 0"
     ],
     indirect=True)
 def test_drivers_release_resources(call_ray_start):
@@ -369,26 +369,24 @@ print("success")
 
 
 def test_calling_start_ray_head(call_ray_stop_only):
+
     # Test that we can call ray start with various command line
     # parameters. TODO(rkn): This test only tests the --head code path. We
     # should also test the non-head node code path.
 
-    # Test starting Ray with no arguments.
-    check_call_ray(["start", "--head"])
-    check_call_ray(["stop"])
-
     # Test starting Ray with a redis port specified.
-    check_call_ray(["start", "--head"])
+    check_call_ray(["start", "--head", "--port", "0"])
     check_call_ray(["stop"])
 
     # Test starting Ray with a node IP address specified.
-    check_call_ray(["start", "--head", "--node-ip-address", "127.0.0.1"])
+    check_call_ray(
+        ["start", "--head", "--node-ip-address", "127.0.0.1", "--port", "0"])
     check_call_ray(["stop"])
 
     # Test starting Ray with a system config parameter set.
     check_call_ray([
         "start", "--head", "--system-config",
-        "{\"metrics_report_interval_ms\":100}"
+        "{\"metrics_report_interval_ms\":100}", "--port", "0"
     ])
     check_call_ray(["stop"])
 
@@ -396,45 +394,49 @@ def test_calling_start_ray_head(call_ray_stop_only):
     # specified.
     check_call_ray([
         "start", "--head", "--object-manager-port", "12345",
-        "--node-manager-port", "54321"
+        "--node-manager-port", "54321", "--port", "0"
     ])
     check_call_ray(["stop"])
 
     # Test starting Ray with the worker port range specified.
     check_call_ray([
         "start", "--head", "--min-worker-port", "50000", "--max-worker-port",
-        "51000"
+        "51000", "--port", "0"
     ])
     check_call_ray(["stop"])
 
     # Test starting Ray with the number of CPUs specified.
-    check_call_ray(["start", "--head", "--num-cpus", "2"])
+    check_call_ray(["start", "--head", "--num-cpus", "2", "--port", "0"])
     check_call_ray(["stop"])
 
     # Test starting Ray with the number of GPUs specified.
-    check_call_ray(["start", "--head", "--num-gpus", "100"])
+    check_call_ray(["start", "--head", "--num-gpus", "100", "--port", "0"])
     check_call_ray(["stop"])
 
     # Test starting Ray with redis shard ports specified.
-    check_call_ray(
-        ["start", "--head", "--redis-shard-ports", "6380,6381,6382"])
+    check_call_ray([
+        "start", "--head", "--redis-shard-ports", "6380,6381,6382", "--port",
+        "0"
+    ])
     check_call_ray(["stop"])
 
     # Test starting Ray with all arguments specified.
     check_call_ray([
         "start", "--head", "--redis-shard-ports", "6380,6381,6382",
         "--object-manager-port", "12345", "--num-cpus", "2", "--num-gpus", "0",
-        "--resources", "{\"Custom\": 1}"
+        "--resources", "{\"Custom\": 1}", "--port", "0"
     ])
     check_call_ray(["stop"])
 
     # Test starting Ray with invalid arguments.
     with pytest.raises(subprocess.CalledProcessError):
-        check_call_ray(["start", "--head", "--address", "127.0.0.1:6379"])
+        check_call_ray(
+            ["start", "--head", "--address", "127.0.0.1:6379", "--port", "0"])
     check_call_ray(["stop"])
 
     # Test --block. Killing a child process should cause the command to exit.
-    blocked = subprocess.Popen(["ray", "start", "--head", "--block"])
+    blocked = subprocess.Popen(
+        ["ray", "start", "--head", "--block", "--port", "0"])
 
     wait_for_children_of_pid(blocked.pid, num_children=7, timeout=30)
 
@@ -447,7 +449,8 @@ def test_calling_start_ray_head(call_ray_stop_only):
     assert blocked.returncode != 0, "ray start shouldn't return 0 on bad exit"
 
     # Test --block. Killing the command should clean up all child processes.
-    blocked = subprocess.Popen(["ray", "start", "--head", "--block"])
+    blocked = subprocess.Popen(
+        ["ray", "start", "--head", "--block", "--port", "0"])
     blocked.poll()
     assert blocked.returncode is None
 

python/ray/tests/test_tempfile.py

@@ -42,7 +42,7 @@ def test_tempdir_commandline():
     shutil.rmtree(ray.utils.get_ray_temp_dir(), ignore_errors=True)
     check_call_ray([
         "start", "--head", "--temp-dir=" + os.path.join(
-            ray.utils.get_user_temp_dir(), "i_am_a_temp_dir2")
+            ray.utils.get_user_temp_dir(), "i_am_a_temp_dir2"), "--port", "0"
     ])
     assert os.path.exists(
         os.path.join(ray.utils.get_user_temp_dir(),