Static IPs

Previously, MAAS relied on the DHCP server to allocate its own IP addresses to nodes, using the IP range defined on the relevant cluster interface. This was found to be unreliable since the IPs were only known once the node had booted and requested an address, and had race conditions when the lease expired and another machine was looking for its own IP.

MAAS now defines an additional range on the cluster for static IPs that are allocated by MAAS itself (see cluster-configuration for more information about this).

In normal operation, MAAS will automatically choose and allocate a static IP to any node network interfaces where it knows on which cluster interface that node interface is connected.

The api contains functions to request additional static IPs, which are summarised here:

Sticky IPs

Synopsis:

`POST /api/1.0/nodes/{system_id}/` `op=claim_sticky_ip_address`

Normally, IPs are released back into the pool of available IPs once a node is released by a user. A "Sticky" IP is one which is allocated to an interface on a node that does not change unless the sticky IP is removed. This enables more predictable IPs at the cost of wasting IPs when the node is not in use.

Unmanaged User-allocated IPs

Synopsis:

`GET /api/1.0/ipaddresses/`
`POST /api/1.0/ipaddresses/` `op=release`
`POST /api/1.0/ipaddresses/` `op=reserve`

This API allows users to request an ad-hoc IP address for use in any way they see fit. The IP is not tied to any node in MAAS and is guaranteed not to be in use by MAAS itself.

See the full API documentation for precise technical details.