> 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_dynamic_on.md).

# HEDNS\_DYNAMIC\_ON

`HEDNS_DYNAMIC_ON` enables [Dynamic DNS](https://dns.he.net/) on a record managed by the Hurricane Electric DNS provider. When enabled, HE DNS assigns a DDNS key to the record that can be used with the HE DDNS update API (`https://dyn.dns.he.net/nic/update`).

If a record is already dynamic, its dynamic state is preserved across modifications even without explicitly specifying this modifier.

To set a specific DDNS key, use [`HEDNS_DDNS_KEY()`](/language-reference/record-modifiers/service-provider-specific/hurricane-electric-dns/hedns_ddns_key.md) instead.

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

```javascript
D("example.com", REG_NONE, DnsProvider(DSP_HEDNS),
    A("dyn", "0.0.0.0", HEDNS_DYNAMIC_ON),
    AAAA("dyn6", "::1", HEDNS_DYNAMIC_ON),
);
```

{% endcode %}