Vero Monitor Service

Description

The dns_check probe performs DNS lookups and validates results. Supports record types A, AAAA, CNAME, MX, TXT. Allows custom DNS resolver and expected value assertions.

Config fields

Field	Type	Required	Default	Description
`type`	`string`	Yes	—	Must be `"dns_check"`
`host`	`string`	Yes	—	Domain name to resolve
`recordType`	`string`	No	`"A"`	Record type: `A`, `AAAA`, `CNAME`, `MX`, `TXT`
`resolver`	`string`	No	system resolver	Custom DNS resolver (host or host:port). Defaults to `:53` if no port
`expectedValues`	`string[]`	No	—	DNS values that must be present in the result. Any missing value → `down`

Metrics

Metric	Type	Unit	Description
`vms.dns_check.status`	status	—	`up` or `down`
`vms.dns_check.latency_ms`	gauge	ms	Lookup time

Example config

{
  "type": "dns_check",
  "host": "app.verolabs.co",
  "recordType": "A",
  "expectedValues": ["10.0.0.10"]
}

Notes

CNAME trailing dots are automatically stripped before comparison.
MX records compare hostname only (no priority).