# Dynamic domains

> Bind a device domain and choose internal or public DNS addresses.

Source: https://www.widewired.com/page/docs/dynamic-domains

## Bind a domain

Open **Configuration → Dynamic domains** and select a device. Enter a prefix, choose `ifconfig.earth`, `ipconfig.earth`, or `ddns123.net`, and select a resolution mode. Click **Check availability**, then **Bind**. Changing the prefix or suffix clears the availability result.

Use 1–63 letters, numbers or hyphens, without a leading or trailing hyphen. Each device can bind one domain. Binding checks availability again. The device must be approved and have an address for the selected mode.

## Resolution modes

| Mode | DNS addresses |
| --- | --- |
| Internal addresses only | Device Overlay address |
| Public addresses only | Available public addresses |
| Internal addresses first | Both, with internal addresses first |
| Public addresses first | Both, with public addresses first |

Save mode changes with ✓ or cancel with ✗. Selection and blur do not save. Priority only orders authoritative DNS answers. Resolvers and operating systems may reorder addresses; connection failover is not guaranteed.

Overlay addresses require access to the virtual network. Public access depends on the device service, firewall and port mapping. A domain binding does not configure forwarding.

## Synchronization

Device address changes update DNS automatically. The page shows published IPv4 / IPv6 addresses and the last synchronization time. IPv6 may come from a format-validated device candidate; it is not a public reachability check. Stale public addresses are withdrawn and published again after fresh observations. Blocking a device or suspending its network withdraws DNS while preserving the configuration.

Failed synchronization preserves the binding and retries automatically. Missing addresses show **Waiting for address**. Records have a five-minute TTL; cached records and negative answers may delay visible changes.

## Unbind

Click **Unbind** in the bottom danger section and confirm. After DNS records are successfully removed, you can bind again immediately. Existing resolver caches expire according to their original TTL. To change the name, unbind, enter the new name, check availability and bind.

## Quick troubleshooting

| Symptom | Action |
| --- | --- |
| Domain already in use | Choose another prefix or suffix, then check availability again. |
| Waiting for address | Check the device addresses or save an internal or preferred-address mode. |
| Synchronization or unbinding has not completed | Failed attempts retry automatically. Check the status again later. |
| DNS still returns an old address | Existing caches retain their remaining TTL, up to 300 seconds. Query again after expiration. |