> For the complete documentation index, see [llms.txt](https://docs.dnscontrol.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.dnscontrol.org/language-reference/record-modifiers/service-provider-specific/hurricane-electric-dns/hedns_ddns_key.md).

# HEDNS\_DDNS\_KEY

`HEDNS_DDNS_KEY` enables Dynamic DNS on a record managed by the Hurricane Electric DNS provider and sets a specific DDNS key (token). This implies [`HEDNS_DYNAMIC_ON`](/language-reference/record-modifiers/service-provider-specific/hurricane-electric-dns/hedns_dynamic_on.md).

The DDNS key can then be used with the HE DDNS update API (`https://dyn.dns.he.net/nic/update`) to update the record's value.

**Note:** DDNS keys are **write-only**. dnscontrol sets the key on the provider but cannot read back the current key. This means a key-only change (same record data, new key) will not be detected as a difference. To force an update, also change another field such as the TTL.

{% code title="dnsconfig.js" %}

```javascript
D("example.com", REG_NONE, DnsProvider(DSP_HEDNS),
    A("dyn", "0.0.0.0", HEDNS_DDNS_KEY("my-secret-token")),
    AAAA("dyn6", "::1", HEDNS_DDNS_KEY("another-token")),
);
```

{% endcode %}


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