# MxResolution

!!! info
    This page was generated by extracting information from a JSON Schema
    data file for the API.  It may be missing some information, or otherwise
    suggest approximate or placeholder values based on information in the
    schema file; this is due to limitations on how that data is extracted
    from the underlying Rust code and into the JSON Schema, and then again
    from there and into these docs.

Summary of an MX resolution attempt for a destination.

{{since('dev')}}

This is an object value, with the following properties:


  * `by_preference` - required `object`. MX hostnames grouped by preference. Lower preference is
    preferred. Empty when DNS returned no MX records and the
    resolver synthesised A/AAAA against `domain` directly.

  * `is_domain_literal` - required `boolean`. True if the destination was a domain literal like `[1.2.3.4]`.

  * `is_mx` - required `boolean`. True if real MX records were found in DNS. False when the
    resolver synthesised an A/AAAA lookup against the domain.

  * `is_secure` - required `boolean`. True if the DNS result was DNSSEC validated.

  * `site_name` - required `string`. Canonical site name; the value used as the queue grouping
    key for this destination.

### Examples
```json
{
  "by_preference": {},
  "is_domain_literal": false,
  "is_mx": false,
  "is_secure": false,
  "site_name": "string"
}
```
