Monitor types

A monitor is a single target that Elerio checks on a schedule. The monitor type defines how the check is performed. Six types are available.

HTTP(S)

The most common type — for websites and APIs. Elerio sends a request to the given URL and considers the target up if the response matches your expectations.

Configurable:

• Method — GET, HEAD, POST and others.
• Expected status code — for example 200. By default any 2xx/3xx counts as success.
• Expected text — a substring that must be present in the response.
• Regular expression — the response must match a pattern.
• JSONPath — check a specific field in a JSON response.
• Response-time threshold — if the response is slower than the limit, the monitor goes Down.
• Headers and request body — for authorized endpoints and POST checks.

Beyond availability, Elerio records the response time of every check and builds history from it.

TCP port

Checks that a given TCP port is open on the host (for example a database, mail or game server). Just provide the host and port — Elerio considers the target up if the connection succeeds.

ICMP ping

A network-reachability check over ICMP (a plain "ping"). Good for network gear and servers with no TCP ports exposed — routers, switches, gateways, printers. Provide only the host.

TLS certificate

Watches the expiry of a TLS/SSL certificate. Provide the host and port (default 443). Elerio:

• warns ahead of time, around two weeks before expiry;
• moves the monitor to Down when 7 days or fewer remain, or the certificate is already expired or invalid.

The monitor card shows how many days are left until expiry.

DNS records

Checks that a DNS record exists and contains the expected values. Provide the host, the record type (A, AAAA, CNAME, NS, MX, TXT) and, optionally, the expected values. Useful for catching a hijacked or missing record.

Heartbeat (passive monitoring)

The inverted model: instead of Elerio reaching out to you, you ping Elerio. For a heartbeat monitor Elerio gives you a personal URL like:

https://elerio.app/api/heartbeat/<your-token>

Ping it (with a GET or POST request) from a cron job, a backup script or the end of a batch process. As long as pings arrive within the declared interval, the monitor is Up. A missing ping triggers an alert.

# example: at the end of a nightly backup script
curl -fsS https://elerio.app/api/heartbeat/<your-token>

This is the only reliable way to learn that a scheduled job never ran at all. If the token is compromised you can regenerate it — the old URL stops working immediately.

Common settings

These apply to monitors of any type.

• Check interval — how often to poll the target. The minimum depends on your plan.
• Timeout — how long to wait for a response before the check counts as failed.
• Double-check before signalling "down". A monitor only goes Down after two consecutive failed checks. This smooths over brief network glitches and cuts down on false alarms.
• Groups — monitors can be grouped by project or client.
• Pause — temporarily stop checks without deleting the monitor.

History and incidents

Every monitor has a history page of its checks and response time. When a monitor goes down, an incident opens with a start time; when it recovers, the incident closes. All incidents are collected on a dedicated page so you can see the whole picture.