fix agent-polled devices stuck in unknown status

store_monitoring_check saved ping results from agents but never
updated device status. DeviceMonitorWorker skips agent-assigned
devices, so nothing ever moved them from :unknown to :up/:down.

added update_device_status_from_check to derive status from check
result, update the device, create alerts on transitions, and
broadcast via PubSub — matching DeviceMonitorWorker behavior.

CHANGELOG.txt

@@ -1,6 +1,17 @@
 CHANGELOG - towerops-web
 ========================
 
+2026-02-11 - fix: update device status from agent monitoring checks
+  - File: lib/towerops_web/channels/agent_channel.ex (store_monitoring_check/2)
+  - Bug: Devices polled by remote agents stayed in "unknown" state because
+    store_monitoring_check saved the ping result but never called
+    Devices.update_device_status/2. The DeviceMonitorWorker (Phoenix-side)
+    skips agent-assigned devices entirely, so nothing ever updated status.
+  - Fix: Added update_device_status_from_check/2 and handle_agent_status_change/3
+    to derive :up/:down from check status, update device, create alerts on
+    transitions, and broadcast via PubSub — matching DeviceMonitorWorker behavior
+  - Also added alias Towerops.Alerts to the channel module
+
 2026-02-11 - fix: update last_snmp_poll_at for agent-polled devices
   - File: lib/towerops_web/channels/agent_channel.ex (process_polling_result/3)
   - Bug: Devices polled by remote agents showed "Last Polled: Never" because

lib/towerops_web/channels/agent_channel.ex

@@ -30,6 +30,7 @@ defmodule ToweropsWeb.AgentChannel do
   alias Towerops.Agent.SnmpQuery
   alias Towerops.Agent.Validator
   alias Towerops.Agents
+  alias Towerops.Alerts
   alias Towerops.Devices
   alias Towerops.Devices.BackupRequests
   alias Towerops.Devices.MikrotikBackups
@@ -1163,6 +1164,7 @@ defmodule ToweropsWeb.AgentChannel do
 
       case Monitoring.create_check(attrs) do
         {:ok, _check} ->
+          update_device_status_from_check(device, status)
           :ok
 
         {:error, changeset} ->
@@ -1184,6 +1186,74 @@ defmodule ToweropsWeb.AgentChannel do
     end
   end
 
+  defp update_device_status_from_check(device, check_status) do
+    new_status = if check_status in [:success, :up, :ok], do: :up, else: :down
+    old_status = device.status
+
+    Devices.update_device_status(device, new_status)
+
+    if old_status != new_status do
+      handle_agent_status_change(device, old_status, new_status)
+    end
+
+    Phoenix.PubSub.broadcast(
+      Towerops.PubSub,
+      "device:#{device.id}",
+      {:device_status_changed, device.id, new_status, nil}
+    )
+  end
+
+  defp handle_agent_status_change(device, _old_status, :down) do
+    if !Alerts.has_active_alert?(device.id, :device_down) do
+      now = DateTime.truncate(DateTime.utc_now(), :second)
+
+      message =
+        if device.snmp_enabled,
+          do: "Device is not responding to SNMP",
+          else: "Device is not responding to ping"
+
+      Alerts.create_alert(%{
+        device_id: device.id,
+        alert_type: :device_down,
+        triggered_at: now,
+        message: message
+      })
+
+      Phoenix.PubSub.broadcast(
+        Towerops.PubSub,
+        "alerts:new",
+        {:new_alert, device.id, :device_down}
+      )
+    end
+  end
+
+  defp handle_agent_status_change(device, _old_status, :up) do
+    now = DateTime.truncate(DateTime.utc_now(), :second)
+
+    message =
+      if device.snmp_enabled,
+        do: "Device is now responding to SNMP",
+        else: "Device is now responding to ping"
+
+    Alerts.create_alert(%{
+      device_id: device.id,
+      alert_type: :device_up,
+      triggered_at: now,
+      message: message
+    })
+
+    case Alerts.get_active_alert(device.id, :device_down) do
+      nil -> :ok
+      alert -> Alerts.resolve_alert(alert)
+    end
+
+    Phoenix.PubSub.broadcast(
+      Towerops.PubSub,
+      "alerts:resolved",
+      {:alert_resolved, device.id, :device_down}
+    )
+  end
+
   defp fetch_device(device_id) do
     case Devices.get_device_with_details(device_id) do
       nil -> {:error, :device_not_found}