About MAAS

MAAS is an open-source tool that lets you create a data centre from bare-metal servers. You can discover, commission, deploy, and dynamically reconfigure a large network of individual units. MAAS converts your hardware investment into a cohesive, flexible, distributed data centre, with a minimum of time and effort.

This section will answer a few questions:

What is MAAS?

MAAS expands to “Metal As A Service” – it converts bare-metal servers into cloud instances of virtual machines. There is no need to manage individual units. You can quickly provision or destroy machines, as if they were instances hosted in a public cloud like Amazon AWS, Google GCE, or Microsoft Azure.

MAAS can act as a standalone PXE/preseed service or integrate with other technologies. It works exceptionally well with Juju, the service and model management tool. MAAS manages the machines and Juju manages the services running on those machines – a perfect arrangement. Virtual machines (VMs) can even act as MAAS machines if they boot from the network via PXE.

Tell me about PXE booting

PXE stands for “Preboot Execution Environment,” usually pronounced “pixie.” The term refers to a way of booting an OS image (or other software assembly) downloaded to a client via a NIC. The NIC must be PXE-capable for this to work. Many NICs can be configured to support PXE boot with a software switch.

What MAAS offers

MAAS can manage a large number of physical machines by merging them into user-defined resource pools. MAAS automatically provisions participating machines and makes them available for use. You can return unused machines to the assigned pool at any time.

MAAS also discovers all of the USB and PCI devices attached to your physical or virtual machines, and allows you to delete them from the machine’s visible configuration, prior to deployment, if you so desire.

MAAS 2.9 does not discover USB and PCI devices. This feature is available from MAAS version 3.0.

A smooth system-management experience

MAAS integrates all the tools you need into a smooth system-management experience. It includes the following thirteen features:

  1. web UI (optimised for mobile devices)
  2. Ubuntu, CentOS, Windows, and RHEL installation support
  3. open-source IP address management (IPAM)
  4. full API/CLI support
  5. high availability (optional)
  6. IPv6 support
  7. inventory of components
  8. DHCP and DNS for other devices on the network
  9. DHCP relay integration
  10. VLAN and fabric support
  11. NTP for the entire infrastructure
  12. hardware testing
  13. composable hardware support

These tools can be controlled from a responsive web UI. You can easily (re)configure and scale your data centre with MAAS.

A smooth system-management experience

MAAS integrates all the tools you need into a smooth system-management experience. It includes the following eleven features:

  1. Ubuntu, CentOS, Windows, and RHEL installation support
  2. open-source IP address management (IPAM)
  3. high availability (optional)
  4. IPv6 support
  5. inventory of components
  6. DHCP and DNS for other devices on the network
  7. DHCP relay integration
  8. VLAN and fabric support
  9. NTP for the entire infrastructure
  10. hardware testing
  11. composable hardware support

MAAS works with any system configuration tools. Both the Chef and Juju teams recommend MAAS as a physical provisioning system.

Please note that Windows and RHEL images require Ubuntu Pro to work correctly with MAAS.

Colocation of key components

MAAS relies on two key components: the region controller and the rack controller. The region controller handles operator requests; the rack controller provides high-bandwidth services to multiple racks. In essence, rack controllers manage racks, while the region controller manages the data centre. We generally recommended installing both controllers on the same system. The default MAAS install delivers this co-located configuration automatically. This all-in-one solution also provides DHCP.

See Concepts and terms for a deeper understanding of these components. Note that in special cases, such as high availability or load balancing, you will want to install multiple region and rack controllers. You should also review your existing network design to determine whether MAAS-managed DHCP will cause problems.