Add Test Framework Support for IPv6-only Management Network

docs/ipv6-management-setup.md

@@ -268,3 +268,52 @@ To switch back to IPv4 management, simply run `deploy-mg` without the `--ipv6-on
 ```
 
 This will regenerate and deploy a minigraph with IPv4-only management configuration.
+
+## Running Tests in IPv6-Only Management Mode
+
+After deploying the DUT with IPv6-only management, you need to run tests with the `-6` flag to ensure the test framework uses IPv6 for management connectivity.
+
+### Using run_tests.sh
+
+Add the `-6` flag to your `run_tests.sh` command:
+
+```bash
+cd tests/
+
+# Basic test execution with IPv6-only management
+./run_tests.sh -6 -n vms-kvm-t0 -d vlab-01 -c bgp/test_bgp_fact.py -f vtestbed.yaml -i ../ansible/veos_vtb
+
+# With additional options
+./run_tests.sh -6 -n vms-kvm-t0 -d vlab-01 -c platform_tests/test_reboot.py -f vtestbed.yaml -i ../ansible/veos_vtb -m individual -t t0,any
+```
+
+### Using pytest directly
+
+Alternatively, use the `--ipv6_only_mgmt` pytest option:
+
+```bash
+pytest --ipv6_only_mgmt \
+    --testbed vms-kvm-t0 \
+    --testbed_file ../ansible/vtestbed.yaml \
+    --inventory ../ansible/veos_vtb \
+    --host-pattern vlab-01 \
+    bgp/test_bgp_fact.py
+```
+
+### What the `-6` flag does
+
+When IPv6-only management mode is enabled:
+
+1. **Management IP**: `dut.mgmt_ip` returns the IPv6 address (`ansible_hostv6`) instead of IPv4 (`ansible_host`)
+2. **Sanity Checks**: The IPv4 management ping check is skipped when `mgmt_ip` is an IPv6 address
+3. **Reboot Operations**: Ping commands use `ping6` for IPv6 management addresses
+4. **Connection Handling**: All SSH connections use the IPv6 management address
+
+### Verifying IPv6-Only Mode
+
+You can verify tests are running in IPv6-only mode by checking the test logs:
+
+```
+INFO  Using IPv6-only management mode: using fec0::ffff:afa:1 as mgmt_ip for vlab-01
+INFO  vlab-01 is using IPv6 management address (fec0::ffff:afa:1). Skip the ipv4 mgmt reachability check.
+```

docs/testbed/README.testbed.VsSetup.md

@@ -550,6 +550,27 @@ If neighbor devices are SONiC
 
 You should see three sets of tests run and pass. You're now set up and ready to use the KVM testbed!
 
+### Running Tests with IPv6-Only Management
+
+If you deployed the DUT with `--ipv6-only-mgmt` (see [IPv6-Only Management Network](#ipv6-only-management-network-optional)), you must run tests with the `-6` flag:
+
+```
+./run_tests.sh -6 -n vms-kvm-t0 -d vlab-01 -c bgp/test_bgp_fact.py -f vtestbed.yaml -i ../ansible/veos_vtb
+```
+
+The `-6` flag tells the test framework to:
+- Use the IPv6 address (`ansible_hostv6`) as the DUT management IP
+- Skip IPv4 management connectivity checks
+- Use `ping6` for reachability tests
+
+Alternatively, you can use pytest directly with the `--ipv6_only_mgmt` option:
+
+```
+pytest --ipv6_only_mgmt --testbed vms-kvm-t0 --testbed_file vtestbed.yaml --inventory ../ansible/veos_vtb --host-pattern vlab-01 bgp/test_bgp_fact.py
+```
+
+For more details, see [IPv6 Management Setup Guide](../ipv6-management-setup.md#running-tests-in-ipv6-only-management-mode).
+
 ## Restore/Remove the testing environment
 If you want to clear your testing environment, you can log into your mgmt docker that you created at step three in section [README.testbed.VsSetup.md#prepare-testbed-host](README.testbed.VsSetup.md#prepare-testbed-host).
 

tests/common/devices/base.py

@@ -9,6 +9,31 @@
 
 logger = logging.getLogger(__name__)
 
+
+# Module-level flag for IPv6-only management mode.
+# This is set by the ipv6_only_mgmt_enabled fixture in conftest.py
+_ipv6_only_mgmt_enabled = False
+
+
+def set_ipv6_only_mgmt(enabled: bool):
+    """Set the IPv6-only management mode flag.
+
+    Called by the ipv6_only_mgmt_enabled fixture in conftest.py.
+    """
+    global _ipv6_only_mgmt_enabled
+    _ipv6_only_mgmt_enabled = enabled
+    if enabled:
+        logger.info("IPv6-only management mode enabled")
+
+
+def is_ipv6_only_mgmt() -> bool:
+    """Check if running in IPv6-only management mode.
+
+    Returns True if --ipv6_only_mgmt pytest option was passed.
+    """
+    return _ipv6_only_mgmt_enabled
+
+
 # HACK: This is a hack for issue https://github.com/sonic-net/sonic-mgmt/issues/1941 and issue
 # https://github.com/ansible/pytest-ansible/issues/47
 # Detailed root cause analysis of the issue: https://github.com/sonic-net/sonic-mgmt/issues/1941#issuecomment-670434790
@@ -46,11 +71,20 @@ def __init__(self, ansible_adhoc, hostname, *args, **kwargs):
             self.host = ansible_adhoc(connection='local', host_pattern=hostname)[hostname]
         else:
             self.host = ansible_adhoc(become=True, *args, **kwargs)[hostname]
-            self.mgmt_ip = self.host.options["inventory_manager"].get_host(hostname).vars["ansible_host"]
-            if "ansible_hostv6" in self.host.options["inventory_manager"].get_host(hostname).vars:
-                self.mgmt_ipv6 = self.host.options["inventory_manager"].get_host(hostname).vars["ansible_hostv6"]
+            host_vars = self.host.options["inventory_manager"].get_host(hostname).vars
+            ansible_host = host_vars.get("ansible_host")
+            ansible_hostv6 = host_vars.get("ansible_hostv6")
+
+            # In IPv6-only management mode, use IPv6 address as the primary mgmt_ip
+            if is_ipv6_only_mgmt() and ansible_hostv6:
+                self.mgmt_ip = ansible_hostv6
+                self.mgmt_ipv6 = ansible_hostv6
+                # Keep IPv4 available for reference but it won't be used for connectivity
+                self._mgmt_ipv4 = ansible_host
+                logger.debug("IPv6-only management mode: using %s as mgmt_ip for %s", ansible_hostv6, hostname)
             else:
-                self.mgmt_ipv6 = None
+                self.mgmt_ip = ansible_host
+                self.mgmt_ipv6 = ansible_hostv6
         self.hostname = hostname
 
     def __getattr__(self, module_name):

tests/common/plugins/sanity_check/checks.py

@@ -1137,6 +1137,13 @@ def _check_ipv4_mgmt_to_dut(*args, **kwargs):
             results[dut.hostname] = check_result
             return
 
+        # Skip IPv4 check if mgmt_ip is an IPv6 address (IPv6-only management mode)
+        if is_ipv6_address(dut.mgmt_ip):
+            logger.info("%s is using IPv6 management address (%s). Skip the ipv4 mgmt reachability check."
+                        % (dut.hostname, dut.mgmt_ip))
+            results[dut.hostname] = check_result
+            return
+
         # most of the testbed should reply within 10 ms, Set the timeout to 2 seconds to reduce the impact of delay.
         try:
             shell_result = localhost.shell("ping -c 2 -W 2 " + dut.mgmt_ip)

tests/common/reboot.py

@@ -769,7 +769,9 @@ def ssh_connection_with_retry(localhost, host_ip, port, delay, timeout):
 
 def collect_mgmt_config_by_console(duthost, localhost):
     logger.info("check if dut is pingable")
-    localhost.shell(f"ping -c 5 {duthost.mgmt_ip}", module_ignore_errors=True)
+    # Use ping6 for IPv6 addresses, ping for IPv4
+    ping_cmd = "ping6" if ":" in str(duthost.mgmt_ip) else "ping"
+    localhost.shell(f"{ping_cmd} -c 5 {duthost.mgmt_ip}", module_ignore_errors=True)
 
     logger.info("Start: collect mgmt config by console")
     creds = creds_on_dut(duthost)

tests/conftest.py

@@ -131,6 +131,8 @@
 def pytest_addoption(parser):
     parser.addoption("--testbed", action="store", default=None, help="testbed name")
     parser.addoption("--testbed_file", action="store", default=None, help="testbed file name")
+    parser.addoption("--ipv6_only_mgmt", action="store_true", default=False,
+                     help="Use IPv6-only management network. DUT mgmt_ip will be set to IPv6 address.")
     parser.addoption("--uhd_config", action="store", help="Enable UHD config mode")
     parser.addoption("--save_uhd_config", action="store_true", help="Save UHD config mode")
     parser.addoption("--npu_dpu_startup", action="store_true", help="Startup NPU and DPUs and install configurations")
@@ -344,6 +346,28 @@ def pytest_configure(config):
             config.pluginmanager.register(MacsecPluginT0())
 
 
+@pytest.fixture(scope="session")
+def ipv6_only_mgmt_enabled(request):
+    """
+    Fixture to check and configure IPv6-only management mode.
+
+    When --ipv6_only_mgmt is passed to pytest (or -6 to run_tests.sh),
+    this enables IPv6-only management mode where DUT mgmt_ip will use
+    the IPv6 address (ansible_hostv6) instead of IPv4 (ansible_host).
+
+    This fixture must be used before duthosts fixture to ensure the
+    mode is configured before SonicHost objects are created.
+
+    Returns:
+        bool: True if IPv6-only management mode is enabled, False otherwise.
+    """
+    from tests.common.devices.base import set_ipv6_only_mgmt
+
+    enabled = request.config.getoption("ipv6_only_mgmt", default=False)
+    set_ipv6_only_mgmt(enabled)
+    return enabled
+
+
 @pytest.fixture(scope="session", autouse=True)
 def enhance_inventory(request, tbinfo):
     """
@@ -517,7 +541,7 @@ def pytest_sessionfinish(session, exitstatus):
 
 
 @pytest.fixture(name="duthosts", scope="session")
-def fixture_duthosts(enhance_inventory, ansible_adhoc, tbinfo, request):
+def fixture_duthosts(enhance_inventory, ansible_adhoc, tbinfo, request, ipv6_only_mgmt_enabled):
     """
     @summary: fixture to get DUT hosts defined in testbed.
     @param enhance_inventory: fixture to enhance the capability of parsing the value of pytest cli argument
@@ -526,6 +550,7 @@ def fixture_duthosts(enhance_inventory, ansible_adhoc, tbinfo, request):
         mandatory argument for the class constructors.
     @param tbinfo: fixture provides information about testbed.
     @param request: pytest request object
+    @param ipv6_only_mgmt_enabled: fixture to configure IPv6-only management mode before DUT initialization
     """
     try:
         host = DutHosts(ansible_adhoc, tbinfo, request, get_specified_duts(request),

tests/run_tests.sh

@@ -31,6 +31,7 @@ function show_help_and_exit()
     echo "    -u             : bypass util group"
     echo "    -w             : warm run, don't clear cache before running tests"
     echo "    -x             : print commands and their arguments as they are executed"
+    echo "    -6             : IPv6-only management mode (use IPv6 for DUT mgmt connectivity)"
 
     exit $1
 }
@@ -124,6 +125,7 @@ function setup_environment()
     TEST_MAX_FAIL=0
     DPU_NAME="None"
     NO_CLEAR_CACHE="False"
+    IPV6_ONLY_MGMT="False"
 
     export ANSIBLE_CONFIG=${BASE_PATH}/ansible
     export ANSIBLE_LIBRARY=${BASE_PATH}/ansible/library/
@@ -205,6 +207,10 @@ function setup_test_options()
         PYTEST_COMMON_OPTS="${PYTEST_COMMON_OPTS} --allow_recover"
     fi
 
+    if [[ x"${IPV6_ONLY_MGMT}" == x"True" ]]; then
+        PYTEST_COMMON_OPTS="${PYTEST_COMMON_OPTS} --ipv6_only_mgmt"
+    fi
+
     for skip in ${SKIP_SCRIPTS} ${SKIP_FOLDERS}; do
         if [[ $skip == *"::"* ]]; then
             PYTEST_COMMON_OPTS="${PYTEST_COMMON_OPTS} --deselect=${skip}"
@@ -314,15 +320,15 @@ function pre_post_extra_params()
 function prepare_dut()
 {
     echo "=== Preparing DUT for subsequent tests ==="
-    echo Running: ${PYTEST_EXEC} ${PYTEST_UTIL_OPTS} ${PRET_LOGGING_OPTIONS} ${UTIL_TOPOLOGY_OPTIONS} $(pre_post_extra_params) -m pretest
-    ${PYTEST_EXEC} ${PYTEST_UTIL_OPTS} ${PRET_LOGGING_OPTIONS} ${UTIL_TOPOLOGY_OPTIONS} $(pre_post_extra_params) -m pretest
+    echo Running: ${PYTEST_EXEC} . ${PYTEST_UTIL_OPTS} ${PRET_LOGGING_OPTIONS} ${UTIL_TOPOLOGY_OPTIONS} $(pre_post_extra_params) -m pretest
+    ${PYTEST_EXEC} . ${PYTEST_UTIL_OPTS} ${PRET_LOGGING_OPTIONS} ${UTIL_TOPOLOGY_OPTIONS} $(pre_post_extra_params) -m pretest
 }
 
 function cleanup_dut()
 {
     echo "=== Cleaning up DUT after tests ==="
-    echo Running: ${PYTEST_EXEC} ${PYTEST_UTIL_OPTS} ${POST_LOGGING_OPTIONS} ${UTIL_TOPOLOGY_OPTIONS} $(pre_post_extra_params) -m posttest
-    ${PYTEST_EXEC} ${PYTEST_UTIL_OPTS} ${POST_LOGGING_OPTIONS} ${UTIL_TOPOLOGY_OPTIONS} $(pre_post_extra_params) -m posttest
+    echo Running: ${PYTEST_EXEC} . ${PYTEST_UTIL_OPTS} ${POST_LOGGING_OPTIONS} ${UTIL_TOPOLOGY_OPTIONS} $(pre_post_extra_params) -m posttest
+    ${PYTEST_EXEC} . ${PYTEST_UTIL_OPTS} ${POST_LOGGING_OPTIONS} ${UTIL_TOPOLOGY_OPTIONS} $(pre_post_extra_params) -m posttest
 }
 
 function run_group_tests()
@@ -423,7 +429,7 @@ for arg in "$@"; do
     fi
 done
 
-while getopts "h?a:b:Bc:C:d:e:Ef:F:H:i:I:k:l:m:n:oOp:q:rs:S:t:uxw" opt; do
+while getopts "h?a:b:Bc:C:d:e:Ef:F:H:i:I:k:l:m:n:oOp:q:rs:S:t:uxw6" opt; do
     case ${opt} in
         h|\? )
             show_help_and_exit 0
@@ -513,6 +519,9 @@ while getopts "h?a:b:Bc:C:d:e:Ef:F:H:i:I:k:l:m:n:oOp:q:rs:S:t:uxw" opt; do
         x )
             set -x
             ;;
+        6 )
+            IPV6_ONLY_MGMT="True"
+            ;;
     esac
 done