diff --git a/bin/tests/system/dnstap/tests_sh_dnstap.py b/bin/tests/system/dnstap/tests_sh_dnstap.py
index 5d4d7a9e9e..d1de2e0efa 100644
--- a/bin/tests/system/dnstap/tests_sh_dnstap.py
+++ b/bin/tests/system/dnstap/tests_sh_dnstap.py
@@ -26,5 +26,6 @@ pytestmark = pytest.mark.extra_artifacts(
 )
 
 
+@isctest.mark.flaky(max_runs=2, rerun_filter=isctest.mark.is_host_freebsd_13)
 def test_dnstap(run_tests_sh):
     run_tests_sh()
diff --git a/bin/tests/system/isctest/mark.py b/bin/tests/system/isctest/mark.py
index 115d68ac51..25408977d7 100644
--- a/bin/tests/system/isctest/mark.py
+++ b/bin/tests/system/isctest/mark.py
@@ -13,6 +13,7 @@
 
 import os
 from pathlib import Path
+import platform
 import shutil
 import ssl
 import subprocess
@@ -54,6 +55,10 @@ def is_dnsrps_available():
     return True
 
 
+def is_host_freebsd_13(*_):
+    return platform.system() == "FreeBSD" and platform.release().startswith("13")
+
+
 have_libxml2 = pytest.mark.skipif(
     not feature_test("--have-libxml2"), reason="libxml2 support disabled in the build"
 )
diff --git a/bin/tests/system/timeouts/tests_tcp_timeouts.py b/bin/tests/system/timeouts/tests_tcp_timeouts.py
index 1750715ce0..1fe1088a69 100644
--- a/bin/tests/system/timeouts/tests_tcp_timeouts.py
+++ b/bin/tests/system/timeouts/tests_tcp_timeouts.py
@@ -13,7 +13,6 @@
 
 # pylint: disable=unused-variable
 
-import platform
 import socket
 import time
 
@@ -68,11 +67,7 @@ def test_initial_timeout(named_port):
                 raise EOFError from e
 
 
-def is_host_freebsd_13(*_):
-    return platform.system() == "FreeBSD" and platform.release().startswith("13")
-
-
-@isctest.mark.flaky(max_runs=2, rerun_filter=is_host_freebsd_13)
+@isctest.mark.flaky(max_runs=2, rerun_filter=isctest.mark.is_host_freebsd_13)
 def test_idle_timeout(named_port):
     #
     # The idle timeout is 5 seconds, so the third message should fail