.. mkh1590590274215 .. _configuration-and-management-storage-on-controller-hosts: =========================== Storage on Controller Hosts =========================== The controllers provide storage for the OpenStack Controller Services through a combination of local container ephemeral disk, Persistent Volume Claims backed by Ceph and a containerized HA mariadb deployment. On systems configured for controller storage with a small Ceph cluster on the master/controller nodes, they also provide persistent block storage for persistent |VM| volumes \(Cinder\), storage for |VM| images \(Glance\), and storage for |VM| remote ephemeral volumes \(Nova\). On All-in-One Simplex or Duplex systems, the controllers also provide nova- local storage for ephemeral |VM| volumes. On systems configured for controller storage, the master/controller's root disk is reserved for system use, and additional disks are required to support the small Ceph cluster. On a All-in-One Simplex or Duplex system, you have the option to partition the root disk for the nova-local storage \(to realize a two-disk controller\) or use a third disk for nova-local storage. .. _configuration-and-management-storage-on-controller-hosts-section-rvx-vwc-vlb: -------------------------------------- Underlying Platform Filesystem Storage -------------------------------------- See the :ref:`platform Planning ` documentation for details. To pass the disk-space checks, any replacement disks must be installed before the allotments are changed. .. _configuration-and-management-storage-on-controller-hosts-section-wgm-gxc-vlb: --------------------------------------- Glance, Cinder, and Remote Nova storage --------------------------------------- On systems configured for controller storage with a small Ceph cluster on the master/controller nodes, this small Ceph cluster on the controller provides Glance image storage, Cinder block storage, Cinder backup storage, and Nova remote ephemeral block storage. For more information, see :ref:`Block Storage for Virtual Machines `. .. _configuration-and-management-storage-on-controller-hosts-section-gpw-kxc-vlb: ------------------ Nova-local Storage ------------------ Controllers on |prod-os| Simplex or Duplex systems incorporate the Compute function, and therefore provide **nova- local** storage for ephemeral disks. On other systems, **nova- local** storage is provided by compute hosts. For more information about this type of storage, see :ref:`Storage on Compute Hosts ` and :ref:`Block Storage for Virtual Machines `.