# MX Records

An `MX` record routes email for your domain to a mail server. Each `MX` record has a priority (a preference number) and a mail server hostname. Mail delivery tries the lowest priority number first.

## Fields

| Field | Example | Notes |
| --- | --- | --- |
| Name | `@` | Usually the apex, so mail addresses are `@your-domain`. |
| Type | `MX` |  |
| Priority | `10` | 0 to 65535. ZCP prefers lower values. Required for `MX`. |
| Content | `mail.example.com.` | The mail server hostname. End it with a trailing dot. |
| TTL | `3600` | Seconds. |

`MX` records need a priority. Set it in its own field, not inside the mail server value. The API requires priority for `MX` and rejects it for every other type.

## Create

Console: choose type `MX`, set Priority and the mail server value in their own fields.

```text
@ MX 10 mail.example.com. 3600
```

CLI (`MX` requires `--priority`):

```bash
zcp dns record-create --domain examplecom --name @ --type MX \
  --content mail.example.com. --priority 10 --ttl 3600
```

API (send `priority` as a separate field):

```bash
curl -s -X POST "https://api.zcp.zsoftly.ca/api/dns/domains/examplecom/records" \
  -H "Authorization: Bearer your-token" \
  -H "Content-Type: application/json" \
  -H "Accept: application/json" \
  -d '{ "name": "@", "type": "MX", "content": "mail.example.com.", "priority": 10, "ttl": 3600 }'
```

## Verify

```bash
dig MX example.com +short
# 10 mail.example.com.
```

## Several Mail Servers per Name

A name and type hold several values. Creating a second `MX` record at `@` adds it to the set. Publish a primary and a backup mail server on the same name. Give each its own priority. A lower number is preferred. See [Several values per name and type](https://docs.zcp.zsoftly.ca/public-cloud/dns/records#several-values-per-name-and-type).

## Notes

- Priority is separate. Do not put the number in the value (`10 mail.example.com.`). The console, CLI, and API each take priority in its own field.
- The mail server needs an address. The `MX` target must resolve to an `A` or `AAAA` record. It cannot point at a `CNAME`.
- A `0` priority is valid and is sent correctly.

See also: [TXT records](https://docs.zcp.zsoftly.ca/public-cloud/dns/records/txt) for SPF and DKIM, [Worked examples](https://docs.zcp.zsoftly.ca/public-cloud/dns/examples), [Record types](https://docs.zcp.zsoftly.ca/public-cloud/dns/records)