IP pools
What an IP pool is
Open Network → Devices → IP pools. A pool is one IPv4 subnet, written as a CIDR such as 10.20.0.0/24 or 41.90.0.8/30. Each pool has:
| Field | What it is |
|---|---|
| Name | What your staff call it, e.g. “Estate A PPPoE” |
| Subnet | /16 to /32. A host address is rounded down to its network, so 10.20.0.7/24 is saved as 10.20.0.0/24 |
| Type | Public static, Private PPPoE or Management |
| Router | Optional: the router the subnet lives on |
| Reserved | Optional: addresses no subscriber should get, such as the gateway. One per line, either an address (10.20.0.1) or a range (10.20.0.2-10.20.0.9) |
The network and broadcast addresses are always reserved. A /31 or /32 has neither, so every address in it is usable.
Staff need the nas permission to see pools, and nas create to add, edit or delete one.
Who holds an address
Centipid does not keep a separate list of assignments. It reads them from three places that already exist:
- a subscriber’s Static IP
- an IP binding’s address
- a router’s own address
So the moment you create a pool over a subnet you already use, its page shows who holds what. The save message says how many addresses are in use and how many clashes it found.
The pool page shows used, free and reserved counts, the next free address, and a list of every held or reserved address. A Clash is an address held by two holders at once, or held while reserved. Fix clashes by giving one of the holders a different address.
Giving a subscriber a static IP
On a PPPoE subscriber’s form, fill Static IP or pick a pool under Next free from pool… to fill in the first address that is neither reserved nor held.
When you save:
- An address inside a pool that is reserved or already held is refused, and the message names the holder.
- An address outside every pool saves, but you get a warning naming anyone else who holds it.
- An address the subscriber already had saves as before, even if it clashes, so old clashes never block an unrelated edit. You still get the warning.
The static IP is sent to the router as Framed-IP-Address, exactly as before. Pools change where you pick the address from, not how it reaches RADIUS.
Deleting a pool removes only the pool and its reserved list. Nobody loses their address.
IPv6 subnets are not supported yet.