Bug: test_snmp_interfaces.py failed with AssertionError: tx_err value is 0 not set to 5000

[manish1-arista]

Is it platform specific

generic

Importance or Severity

Medium

Description of the bug

The test case test_snmp_interfaces.py::test_snmp_interfaces_error_discard fails with the following assertion error:

AssertionError: tx_err value is 0 not set to 5000

This issue is only seen on dualtor systems.

Steps to Reproduce

Run the testcase test_snmp_interfaces.py::test_snmp_interfaces_error_discard on a dualtor testbed

Actual Behavior and Expected Behavior

Expected Behavior: Both test instances pass (one for each DUT)
Actual Behaviour: First DUT passes, second DUT fails with tx_err value is 0 not set to 5000

Relevant log output

"21/01/2026 08:13:34 test_snmp_interfaces.test_snmp_interface L0405 INFO   | Compare rif counters in COUNTERS DB and counters get from SONiC CLI\n",
        "21/01/2026 08:13:34 test_snmp_interfaces.test_snmp_interface L0411 INFO   | Compare port counters in COUNTERS DB and counters get from SONiC CLI\n",
        "21/01/2026 08:13:34 __init__.pytest_runtest_call             L0040 ERROR  | Traceback (most recent call last):\n",
        "  File \"/usr/local/lib/python3.8/dist-packages/_pytest/python.py\", line 1788, in runtest\n",
        "    self.ihook.pytest_pyfunc_call(pyfuncitem=self)\n",
        "  File \"/usr/local/lib/python3.8/dist-packages/pluggy/_hooks.py\", line 513, in __call__\n",
        "    return self._hookexec(self.name, self._hookimpls.copy(), kwargs, firstresult)\n",
        "  File \"/usr/local/lib/python3.8/dist-packages/pluggy/_manager.py\", line 120, in _hookexec\n",
        "    return self._inner_hookexec(hook_name, methods, kwargs, firstresult)\n",
        "  File \"/usr/local/lib/python3.8/dist-packages/pluggy/_callers.py\", line 139, in _multicall\n",
        "    raise exception.with_traceback(exception.__traceback__)\n",
        "  File \"/usr/local/lib/python3.8/dist-packages/pluggy/_callers.py\", line 103, in _multicall\n",
        "    res = hook_impl.function(*args)\n",
        "  File \"/usr/local/lib/python3.8/dist-packages/_pytest/python.py\", line 194, in pytest_pyfunc_call\n",
        "    result = testfunction(**testargs)\n",
        "  File \"/data/tests/snmp/test_snmp_interfaces.py\", line 412, in test_snmp_interfaces_error_discard\n",
        "    assert int(port_counters['tx_err']) == COUNTER_VALUE, \\\n",
        "AssertionError: tx_err value is 0 not set to 5000\n",

Output of show version

Attach files (if any)

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[vivekverma-arista]

#22108 raised for this issue.