> ## Documentation Index
> Fetch the complete documentation index at: https://docs.centipidbilling.com/llms.txt
> Use this file to discover all available pages before exploring further.

# IP and MAC bindings

> Create and support router-scoped device bindings with reserved addresses.

# Bind a device to network access

A binding associates a subscriber/device MAC with a reserved IP on a specific NAS. It is useful for devices that should bypass the normal Hotspot login while remaining managed by subscriber/package policy.

## Prerequisites

* A configured router exists in **Network → Devices → Routers**.
* The router is reachable enough for device discovery.
* The device has appeared in ARP, DHCP, or Hotspot observations, or you have verified its MAC independently.
* A compatible Hotspot package exists.
* The reserved IP belongs to the intended network and is not already assigned.

## Create a binding

1. Open **Customers → Subscribers**.
2. Choose **New subscriber** and select **Binding**.
3. Enter subscriber identity and contact information.
4. Select the router.
5. Select the observed device after matching MAC, IP, and hostname.
6. Enter the static **IP address**.
7. Add **Range end** only for a deliberate multi-address pool.
8. Select the compatible package and review expiry.
9. Enable SMS expiry reminders only when a valid phone and reminder configuration exist.
10. Save and test from the actual device.

## Legacy routes

Older `/ip-bindings` links redirect to the Bindings view inside Subscribers. Use the current subscriber workspace for new documentation, bookmarks, and support instructions.

## Troubleshooting

### Router picker is empty

No NAS is configured or the current user lacks router access. Provision the router or ask an administrator to review permissions.

### Device list is empty

Connect the device to the intended network, generate traffic, confirm router reachability, and refresh the picker. Do not invent a MAC address from a different interface label.

### Binding saves but device has no access

Check the MAC normalization, reserved IP/subnet, package status, expiry, router selection, IP conflict, and Hotspot/bypass configuration. Review active sessions and router diagnostics.

### Wrong device was selected

Edit or disable the binding immediately, verify the correct device owner, and inspect whether another subscriber was affected. Avoid recycling a reserved IP until stale network state clears.