Alert Types
Detailed guide to all available alert types for each monitoring module.
VitalSentinel supports alerts across all monitoring modules. This guide covers every available alert type and when to use them.
Uptime Alerts
Uptime Monitoring alerts use predefined configurations. Select from these available alert types:
Available Presets
| Alert | Severity | Description |
|---|---|---|
| Site is down | Critical | Triggers when site becomes unreachable |
| Site is up (after was down) | Critical | Triggers when site recovers |
| SSL will expire in 30 days | Warning | Early SSL expiration warning |
| SSL will expire in 14 days | Warning | SSL expiration warning |
| SSL will expire in 7 days | Critical | Urgent SSL expiration |
| Domain will expire in 30 days | Warning | Early domain expiration warning |
| Domain will expire in 14 days | Warning | Domain expiration warning |
| Domain will expire in 7 days | Critical | Urgent domain expiration |
RUM Alerts
RUM Monitoring tracks real user performance metrics. See Performance Thresholds for detailed rating breakdowns.
LCP (Largest Contentful Paint)
| Threshold | Rating |
|---|---|
| ≤ 2500ms | Good |
| 2500-4000ms | Needs Improvement |
| > 4000ms | Poor |
Example:
If LCP p75 > 2500ms → Warning
If LCP p75 > 4000ms → CriticalCLS (Cumulative Layout Shift)
| Threshold | Rating |
|---|---|
| ≤ 0.1 | Good |
| 0.1-0.25 | Needs Improvement |
| > 0.25 | Poor |
Example:
If CLS p75 > 0.1 → Warning
If CLS p75 > 0.25 → CriticalINP (Interaction to Next Paint)
| Threshold | Rating |
|---|---|
| ≤ 200ms | Good |
| 200-500ms | Needs Improvement |
| > 500ms | Poor |
Example:
If INP p75 > 200ms → Warning
If INP p75 > 500ms → CriticalTTFB (Time to First Byte)
| Threshold | Rating |
|---|---|
| ≤ 800ms | Good |
| 800-1800ms | Needs Improvement |
| > 1800ms | Poor |
Example:
If TTFB p75 > 800ms → WarningFCP (First Contentful Paint)
| Threshold | Rating |
|---|---|
| ≤ 1800ms | Good |
| 1800-3000ms | Needs Improvement |
| > 3000ms | Poor |
Example:
If FCP p75 > 1800ms → WarningCWV Good Experiences
Percentage of page views with all Core Web Vitals (LCP, CLS, INP) rated "Good".
Example:
If CWV Good Percentage < 75% → WarningError Rate
Percentage of page views with JavaScript errors.
Example:
If Error Rate > 5% → WarningCrUX Alerts
CrUX Monitoring tracks Chrome User Experience Report data with custom threshold alerts.
Available Metrics
| Metric | Good | Needs Improvement | Poor |
|---|---|---|---|
| LCP p75 | ≤ 2500ms | 2500-4000ms | > 4000ms |
| CLS p75 | ≤ 0.1 | 0.1-0.25 | > 0.25 |
| INP p75 | ≤ 200ms | 200-500ms | > 500ms |
| TTFB p75 | ≤ 800ms | 800-1800ms | > 1800ms |
Configuration Options
- URL/Origin: Monitor specific URL or entire origin
- Device: Any, Phone, or Desktop
Example:
If LCP p75 > 2500ms (Origin, Any device) → Warning
If INP p75 > 200ms (Origin, Phone) → WarningCrUX data is based on real user metrics collected over 28 days.
Synthetic Alerts
Synthetic Monitoring runs Lighthouse tests with custom thresholds.
Available Metrics
| Metric | Default Threshold | Description |
|---|---|---|
| TTFB | 800ms | Time to First Byte |
| FCP | 1800ms | First Contentful Paint |
| SI | 3400ms | Speed Index |
| LCP | 2500ms | Largest Contentful Paint |
| TTI | 3800ms | Time to Interactive |
| TBT | 200ms | Total Blocking Time |
| CLS | 0.1 | Cumulative Layout Shift |
| Network Requests | 100 | Total network requests |
Configuration Options
- URL: Select which monitored URL to track
- Device: Any, Phone, or Desktop
- Evaluation Window: Average of last 1, 3, 5, or 10 tests
Example:
If LCP > 2500ms (avg last 5 tests) → Warning
If TBT > 200ms (avg last 3 tests) → Warning
If CLS > 0.1 (last test) → CriticalRobots.txt Alerts
Robots.txt Monitoring alerts use predefined configurations. Select from these available alert types:
Available Presets
| Alert | Severity | Description |
|---|---|---|
| Robots.txt file changed | Info | Notifies when file content changes |
| Robots.txt has syntax errors | Critical | Triggers when parsing errors detected |
| Robots.txt blocks sitemap URLs | Warning | Triggers when robots.txt blocks URLs from sitemap |
Recommended Alert Sets
Use the Create essential alerts with one click feature in the Alerts page to automatically create these recommended alerts.
What Gets Created
RUM Monitoring (p75 within last 24h, Warning, in-app only):
- LCP > 2.5s
- CLS > 0.1
- INP > 200ms
CrUX Monitoring (p75 within last 7 days, Origin, Warning, in-app only):
- LCP > 2.5s
- CLS > 0.1
- INP > 200ms
Synthetic Monitoring (Home URL, avg of last 5 tests, Warning, in-app only):
- LCP > 2.5s
- CLS > 0.1
Uptime Monitoring (Critical, with email):
- Site is down
- Site is up (recovery)
Robots.txt Monitoring:
- Blocks sitemap URLs (Warning, with email)
- Has syntax errors (Critical, with email)