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Acme

Eight kinds of check

Each one answers a different question about a site. Most people start with the first and add the rest as they discover what actually breaks.

Uptime

A real request to your URL, from outside your network.

Alerts when: Status code outside the range you set, a timeout, a refused connection, a DNS failure or a TLS error.

Keyword

Loads the page and looks for text that must - or must not - be there.

Alerts when: Catches the case a status check cannot: a page returning 200 OK while showing a database error, a blank screen or a suspension notice.

SSL certificate

Opens a TLS connection and reads the certificate itself.

Alerts when: Expiry inside three days, a name that does not cover the host, a self-signed certificate or a broken chain. Warnings start 14 days out.

Domain expiry

Asks the registry directly over RDAP, falling back to WHOIS.

Alerts when: Registration ending within three days. Warnings start 30 days out, which is enough time to renew calmly.

DNS records

Resolves A, AAAA, MX, NS, TXT or CNAME and compares them with what you expect.

Alerts when: A record disappearing or changing - which catches both a botched migration and a hijacked domain.

TCP port

Connects to a specific port: mail, database, SSH, anything listening.

Alerts when: Nothing accepting connections, or a connection that times out.

Ping

ICMP echo to the host, three packets.

Alerts when: All three lost. Useful for servers that answer no HTTP at all.

Heartbeat

Works the other way round: your job calls us when it finishes.

Alerts when: The call not arriving in time. The only way to watch a nightly backup or a cron task with no public address.

What happens when something breaks

We check again before telling you

One failed request never raises an alert. We re-check 30 seconds later, and only a confirmed failure counts. Before believing any failure we also verify our own connectivity against reference hosts - and if more than a third of everything we watch fails at once, we assume the fault is ours, hold every alert and wake our own operators instead.

Then we reach you where you actually are

Email, Telegram, Slack, Discord and signed webhooks. Quiet hours hold back certificate and domain reminders, but never an outage. A monitor flapping up and down is collapsed into one message instead of fifty.

And your client can check for themselves

A public status page, on your client's own domain if you want, showing the services you choose under names you choose. They stop emailing you to ask whether the site is down.

With proof afterwards

Uptime history, incident records with causes and durations, and reports you can schedule straight to the client on the first of every month.

Ten monitors, free forever

No card, and commercial use is allowed.

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