Suppress initial interface down alarms with config option

changelog.d/257.added.md

@@ -0,0 +1 @@
+Add config option to suppress initial interface down events

src/zino/config/models.py

@@ -71,6 +71,7 @@ class Polling(BaseModel):
 
     file: ExistingFileName = POLLFILE
     period: int = 1
+    suppress_initial_down_alarms: bool = False
 
 
 class Configuration(BaseModel):

src/zino/tasks/linkstatetask.py

@@ -7,6 +7,7 @@
 from zino.oid import OID
 from zino.scheduler import get_scheduler
 from zino.snmp import SparseWalkResponse
+from zino.state import config
 from zino.statemodels import InterfaceState, Port, PortStateEvent
 from zino.tasks.task import Task
 
@@ -117,6 +118,10 @@ def _update_state(self, data: BaseInterfaceRow, port: Port, row: dict[str, Any])
     def _make_or_update_state_event(self, port: Port, new_state: InterfaceState, last_change: int):
         event = self.state.events.get_or_create_event(self.device.name, port.ifindex, PortStateEvent)
 
+        if config.polling.suppress_initial_down_alarms and not event.id and new_state == InterfaceState.DOWN:
+            self.schedule_verification_of_single_port(port.ifindex)
+            return
+
         event.portstate = new_state
         event.port = port.ifdescr
         event.ifindex = port.ifindex

tests/tasks/test_linkstatetask.py

@@ -28,6 +28,14 @@ async def test_run_should_create_event_if_at_least_one_link_is_down(self, linkst
         assert (await task.run()) is None
         assert len(task.state.events) == 1
 
+    async def test_run_should_not_create_event_if_suppress_initial_down_alarms_config_is_true(
+        self, linkstatetask_with_one_link_down
+    ):
+        task = linkstatetask_with_one_link_down
+        with patch("zino.state.config.polling.suppress_initial_down_alarms", True):
+            assert (await task.run()) is None
+        assert len(task.state.events) == 0
+
     def test_when_patterns_are_empty_interface_should_not_be_ignored(self, task_with_dummy_device):
         data = BaseInterfaceRow(
             index=2, descr="GigabitEthernet1/2", alias="uplink", admin_status="up", oper_status="up", last_change=0

zino.toml.example

@@ -26,6 +26,10 @@ file = "polldevs.cf"
 # default 1 min
 period = 1
 
+# If on the first start of Zino interface-down alarms should be created
+# default False
+suppress_initial_down_alarms = False
+
 # Logging configuration is optional, but if specified, it will override the
 # default logging config of Zino.  This is a TOML representation of the default
 # logging configuration dictionary, whose full documentation is available at