Check types Beta

A monitor's type decides what it checks. The default is http, a web page, and every monitor created before check types existed is one.

Set type when you create a monitor. It can be changed later with update, along with the settings that type needs.

The nine types

Type	What it checks	Up when	Page
`http`	A web page or endpoint	A 2xx or 3xx response that passes your text checks	Website
`httpcustom`	A status document your endpoint returns	A named field in the JSON or XML holds the value you expect	Custom status page
`tcp`	A TCP port	The port accepts a connection, and any reply you expect arrives	TCP port
`udp`	A UDP port	Something replies to your datagram	UDP port
`ping`	A host, by ICMP echo	The host answers the ping	Ping
`dns`	A DNS record	The name resolves, and the answer matches what you expect	DNS record
`smtp`	A mail server	The server greets you, and signs you in when you ask it to	Mail servers
`pop3`	A mailbox server	The server greets you with `+OK`	Mail servers
`imap`	A mailbox server	The server greets you with `* OK`	Mail servers

Read the live list, with the port and encryption rules for each type, from setting options.

A URL or a host

http and httpcustom take a URL, as before.
Every other type takes a bare host, such as mail.example.com or an IP address. Send it as url (or host, which is accepted too).
A host typed with a scheme or a path is reduced to the host, so https://mail.example.com/inbox is stored as mail.example.com.
A port written into the host is pulled out into port: mail.example.com:587 becomes host mail.example.com and port 587.
The host is stored in url, so list, results and the reports work exactly as they do for a website.

Duplicates

Two monitors clash only when the type, host and port all match. The same domain can have a website check, a mail check and a DNS record check side by side. A clash returns 409.

When ping isn't available

ICMP needs a raw socket, which a container doesn't always allow. Setting options returns pingAvailable so you can tell in advance. On a checking server without it, a ping check reports ICMP isn't available from this checking server rather than calling the host down, and it isn't retried.

What doesn't change

Intervals, retries and alerting work the same way. A failed check is retried up to twice more, four seconds apart, before the monitor counts as down.
Results, reports and maintenance are the same for every type.
Locations (regions) and the certificate settings (verifyCertificate, sslDownDays) apply to the web types only.
Text checks (shouldContain, shouldNotContain), postData and requestHeaders apply to the web types only.

Filtering by type

List monitors takes ?type= with a comma list, and both the list and the detail return type and port.

Monitor settings: every field, including the per-type ones
Create a monitor: set the type when you add one
Setting options: the live list of types, ports and encryptions