sencho/docs/features/alerts-notifications.mdx

---
title: Alerts & Notifications
description: Set threshold-based alerts on container metrics and route them to Discord, Slack, or any webhook.
---

Sencho can watch your containers for resource anomalies and notify you when thresholds are breached. Alerts are defined per stack, and notifications are delivered through external channels you configure.

## Setting up notification channels

At least one channel must be enabled before alerts can be delivered externally. Go to **Settings > Notifications**.

<Frame>
  <img src="/images/alerts-notifications/notifications-settings.png" alt="Notifications & Alerts settings showing Discord, Slack, and Webhook tabs" />
</Frame>

Three channel types are available, each configured with a webhook URL and an enable/disable toggle:

### Discord

1. In Discord, go to your server's **Settings > Integrations > Webhooks**
2. Click **New Webhook**, choose a channel, and copy the webhook URL
3. In Sencho, open **Settings > Notifications > Discord**, paste the URL, enable the toggle, and click **Save**
4. Click **Test** to send a test message and verify the connection

### Slack

1. In Slack, go to **api.slack.com/apps**, create an app, and add the **Incoming Webhooks** feature
2. Activate it and copy the generated webhook URL for your chosen channel
3. In Sencho, open **Settings > Notifications > Slack**, paste the URL, enable the toggle, and click **Save**

### Generic Webhook

Any HTTP endpoint that accepts a POST with a JSON body can receive Sencho alerts. Go to **Settings > Notifications > Webhook**, enter the URL, enable the toggle, and click **Save**.

The payload format is:

```json
{
  "level": "warning",
  "message": "cpu_percent exceeded 90% for 5 minutes on stack my-app",
  "timestamp": "2026-03-22T10:00:00.000Z"
}
```

## Creating stack alerts

Stack alerts are configured per stack. Right-click a stack in the sidebar (or click the three-dot menu) and select **Alerts**. A panel slides open showing existing rules and a form to create new ones.

<Frame>
  <img src="/images/alerts-notifications/alert-panel.png" alt="Stack Alerts panel showing the notification status banner and alert rule form" />
</Frame>

The panel includes:

- **Notification status banner** at the top, showing whether channels are configured. If no channels are enabled, a warning explains that rules will be evaluated but no external notifications will be sent.
- **Existing Rules** section listing all active rules for this stack, each showing the metric, condition, duration, and cooldown. Hover over a rule to reveal the delete button.
- **Add New Rule** form with the fields described below.

### Alert fields

| Field | Description |
|-------|-------------|
| **Metric** | The container metric to watch (see table below) |
| **Operator** | Comparison: Greater than, Greater or equal, Less than, Less or equal, Equals |
| **Threshold** | The numerical value to compare against |
| **Duration (mins)** | How long the condition must hold before firing (default: 5) |
| **Cooldown (mins)** | Minimum time between repeated notifications for this rule (default: 60) |

### Available metrics

| Metric | Description |
|--------|-------------|
| CPU Usage (%) | CPU usage relative to total host cores |
| Memory Usage (%) | Memory used as a fraction of the host total |
| Memory Usage (MB) | RSS memory used by the container |
| Network In (MB) | Inbound network throughput |
| Network Out (MB) | Outbound network throughput |
| Restart Count | Number of times the container has restarted |

### Example: alert on high CPU

To alert when any container in a stack uses more than 80% CPU for over 5 consecutive minutes, with a 60-minute cooldown:

| Field | Value |
|-------|-------|
| Metric | CPU Usage (%) |
| Operator | Greater than |
| Threshold | 80 |
| Duration | 5 |
| Cooldown | 60 |

## Notification history

All dispatched notifications appear in the **notification bell** in the top-right corner of the navigation bar. A red dot pulses on the bell when unread notifications exist.

<Frame>
  <img src="/images/alerts-notifications/notification-popover.png" alt="Notification popover showing recent alert entries with level badges and timestamps" />
</Frame>

Click the bell to open the notification popover, which shows:

- **Level badge** for each entry (ERROR in red, WARNING in amber, INFO in default)
- **Node name** badge for notifications from remote nodes
- **Timestamp** of when the alert was triggered
- **Alert message** describing what was breached

The popover header includes:

| Action | What it does |
|--------|--------------|
| **Mark all as read** | Marks all notifications as read (removes the red dot) |
| **Clear all** | Deletes all notifications from the list |

You can also dismiss individual notifications by hovering over them and clicking the dismiss button.

<Note>
  Notifications only reach external channels (Discord, Slack, Webhook) if at least one channel is enabled. Dashboard notifications appear regardless.
</Note>

## Alerts on remote nodes

Alerts work the same way on remote nodes as they do locally. When you switch to a remote node and open a stack's alerts panel, you are managing rules on that remote instance.

Key details:

- **Alert rules are stored on each node independently.** Rules created while a remote node is selected are saved on that remote instance, not your primary instance.
- **Monitoring runs locally on each node.** Each Sencho instance evaluates its own alert rules against its own container metrics.
- **Notifications are sent by the node that detects the breach.** Make sure notification channels are configured on each remote node where you want to receive alerts, since channel settings are per-instance.

The alert panel shows a blue info banner when you are configuring alerts on a remote node, including which channels are active on that node.

### Setup checklist for remote alerts

1. On the **remote** Sencho instance, go to **Settings > Notifications** and configure at least one channel
2. From your **primary** instance, switch to the remote node
3. Right-click a stack and select **Alerts** to create rules
4. The remote instance handles monitoring and notification delivery independently