diff --git a/nat-lab/tests/conftest.py b/nat-lab/tests/conftest.py
index 6d7382669..d02b6eb6a 100644
--- a/nat-lab/tests/conftest.py
+++ b/nat-lab/tests/conftest.py
@@ -9,7 +9,9 @@
 from helpers import SetupParameters
 from interderp_cli import InterDerpClient
 from itertools import combinations
+from typing import Optional
 from utils.bindings import TelioAdapterType
+from utils.connection import DockerConnection
 from utils.connection_util import ConnectionTag, LAN_ADDR_MAP, new_connection_raw
 from utils.process import ProcessExecError
 from utils.router import IPStack
@@ -25,10 +27,9 @@
 SETUP_CHECK_TIMEOUT_S = 30
 SETUP_CHECK_RETRIES = 5
 
-# pylint: disable=unnecessary-dunder-call
-TEST_SCOPE_ASYNC_EXIT_STACK = asyncio.run(AsyncExitStack().__aenter__())
-# pylint: disable=unnecessary-dunder-call
-SESSION_ASYNC_EXIT_STACK = asyncio.run(AsyncExitStack().__aenter__())
+RUNNER = asyncio.runners.Runner()
+TEST_SCOPE_EXIT_STACK: Optional[AsyncExitStack] = None
+SESSION_SCOPE_EXIT_STACK: Optional[AsyncExitStack] = None
 
 
 def _cancel_all_tasks(loop: asyncio.AbstractEventLoop):
@@ -208,6 +209,9 @@ async def setup_check_interderp():
             ]
         ]
 
+        if not isinstance(connections[0], DockerConnection):
+            raise Exception("Not docker connection")
+
         async with make_tcpdump(connections):
             for idx, (server1, server2) in enumerate(
                 combinations(
@@ -407,9 +411,13 @@ def pytest_runtest_call(item):
     if os.environ.get("NATLAB_SAVE_LOGS") is None:
         return
 
-    async def async_code():
+    async def async_context():
+        global TEST_SCOPE_EXIT_STACK
+        if not TEST_SCOPE_EXIT_STACK:
+            TEST_SCOPE_EXIT_STACK = AsyncExitStack()
+
         connections = [
-            await TEST_SCOPE_ASYNC_EXIT_STACK.enter_async_context(
+            await TEST_SCOPE_EXIT_STACK.enter_async_context(
                 new_connection_raw(conn_tag)
             )
             for conn_tag in [
@@ -417,9 +425,10 @@ async def async_code():
                 ConnectionTag.DOCKER_DNS_SERVER_2,
             ]
         ]
-        await TEST_SCOPE_ASYNC_EXIT_STACK.enter_async_context(make_tcpdump(connections))
 
-    asyncio.run(async_code())
+        await TEST_SCOPE_EXIT_STACK.enter_async_context(make_tcpdump(connections))
+
+    RUNNER.run(async_context())
 
 
 # pylint: disable=unused-argument
@@ -427,14 +436,14 @@ def pytest_runtest_makereport(item, call):
     if os.environ.get("NATLAB_SAVE_LOGS") is None:
         return
 
-    async def async_code():
-        global TEST_SCOPE_ASYNC_EXIT_STACK
-        await TEST_SCOPE_ASYNC_EXIT_STACK.aclose()
-        # pylint: disable=unnecessary-dunder-call
-        TEST_SCOPE_ASYNC_EXIT_STACK = await AsyncExitStack().__aenter__()
+    async def async_context():
+        global TEST_SCOPE_EXIT_STACK
+        if TEST_SCOPE_EXIT_STACK:
+            await TEST_SCOPE_EXIT_STACK.aclose()
+            TEST_SCOPE_EXIT_STACK = None
 
     if call.when == "call":
-        asyncio.run(async_code())
+        RUNNER.run(async_context())
 
 
 # pylint: disable=unused-argument
@@ -442,18 +451,22 @@ def pytest_sessionstart(session):
     if os.environ.get("NATLAB_SAVE_LOGS") is None:
         return
 
-    async def async_code():
+    async def async_context():
+        global SESSION_SCOPE_EXIT_STACK
+        if not SESSION_SCOPE_EXIT_STACK:
+            SESSION_SCOPE_EXIT_STACK = AsyncExitStack()
+
         connections = [
-            await SESSION_ASYNC_EXIT_STACK.enter_async_context(
+            await SESSION_SCOPE_EXIT_STACK.enter_async_context(
                 new_connection_raw(gw_tag)
             )
             for gw_tag in ConnectionTag
             if "_GW" in gw_tag.name
         ]
-        await SESSION_ASYNC_EXIT_STACK.enter_async_context(make_tcpdump(connections))
 
-    if not session.config.option.collectonly:
-        asyncio.run(async_code())
+        await SESSION_SCOPE_EXIT_STACK.enter_async_context(make_tcpdump(connections))
+
+    RUNNER.run(async_context())
 
 
 # pylint: disable=unused-argument
@@ -461,8 +474,14 @@ def pytest_sessionfinish(session, exitstatus):
     if os.environ.get("NATLAB_SAVE_LOGS") is None:
         return
 
+    async def async_context():
+        global SESSION_SCOPE_EXIT_STACK
+        if SESSION_SCOPE_EXIT_STACK:
+            await SESSION_SCOPE_EXIT_STACK.aclose()
+            SESSION_SCOPE_EXIT_STACK = None
+
     if not session.config.option.collectonly:
-        asyncio.run(SESSION_ASYNC_EXIT_STACK.aclose())
+        RUNNER.run(async_context())
         collect_nordderper_logs()
         collect_dns_server_logs()
         asyncio.run(collect_kernel_logs(session.items, "after_tests"))