Monitors overview

A monitor is a single check target. Vantaj runs it on a configurable schedule and records the result of every check.

Adding a monitor

Click New monitor from the Monitors page. Switch the monitor type in the demo below to see how the form adapts:

The basics

Every monitor needs:

• Display name - a human-readable label, e.g. Checkout API
• Target - what to check. A URL for HTTP(s), a host or IP for Ping, host:port for Port, and a mail server address for SMTP
• Monitor type - HTTP(s), Ping (ICMP), Port (TCP), or SMTP
• Check interval - anything from every 30 seconds to once a day (see Check interval below)
• Group (optional) - type a name to organise related monitors together
• Regions - which locations checks run from (see Regions below)

Advanced options for HTTP(s)

HTTP monitors have the deepest configuration:

• HTTP method - GET, POST, PUT, PATCH, HEAD, DELETE, or QUERY
• Request headers - any number of key-value pairs, e.g. an Authorization header for a protected health endpoint
• Request body - for POST, PUT, PATCH, and QUERY requests
• Expected status codes - comma-separated list; defaults to any 2xx
• Response assertions - require the response body to contain or not contain a keyword. Great for catching soft failures where the page loads but shows an error
• Basic auth - username and password sent with each check
• Timeout - 5 seconds to 2 minutes
• Follow redirects and Verify SSL toggles
• Degraded threshold - mark the monitor degraded (without alerting as down) when responses are slower than a millisecond threshold you set

Advanced options for other types

• Ping and Port monitors support the degraded threshold
• SMTP monitors add connection security (None, STARTTLS, or SSL/TLS), an optional EHLO domain, optional auth credentials, and a timeout

Linked monitors

When creating an HTTP monitor, you can enable companion checks in one click:

• SSL certificate expiry - alert before the certificate runs out
• DNS resolution - alert if the hostname stops resolving
• Domain expiry - track the domain's registration under Domains

Each toggle creates a linked monitor alongside the HTTP one, so a single form covers the whole stack of ways a URL can fail.

Status values

Check interval

Checks run at a fixed interval per monitor. Available intervals range from 30 seconds to 24 hours: 30s, 1m, 3m, 5m, 10m, 30m, 1h, 6h, and 24h.

Regions

Checks run from multiple regions - US East, Europe, and Asia Pacific. A monitor's response-time chart breaks results down per region, so you can see where latency is coming from. Checking from more than one place also avoids false alarms caused by a single bad network path.

If your endpoints aren't publicly reachable, allowlist the checker IPs - see Probe IPs & regions.

Alerts

Opening a monitor's Alerts tab lets you attach an alert policy so you're notified when it goes down, degrades, or recovers. A monitor with no policy attached is still checked, but won't notify anyone.

Grouping

You can assign monitors to a group (e.g. Production, Staging, Third-party). Groups are created on the fly - just type a name when creating or editing a monitor. Monitors with a group are displayed under a labelled section header in the list.

History and incidents

Every check result is stored. The History tab on a monitor's detail page shows a scrollable, filterable log of all checks. Incidents are opened automatically when a monitor goes down and resolved when it recovers.

Uptime calculation

Uptime % is calculated as:

uptime = (up checks / total checks) × 100

It is always shown in the context of a selected timeframe (1h, 24h, 7d, 30d, 90d, or custom range).