Appendix C. Environment Details

The undercloud is a server used exclusively by the OpenStack operator to deploy, scale, manage, and life-cycle the overcloud, the cloud that provides services to users. Red Hat’s undercloud product is Red Hat OpenStack Platform director.

The undercloud system hosting Red Hat OpenStack Platform director is a virtual machine running Red Hat Enterprise Linux 7.3 with the following specifications:

The hypervisor which hosts this virtual machine is a Dell M630 with the following specifications:

The hypervisor runs Red Hat Enterprise Linux 7.3 and uses the KVM and Libvirt packages shipped with Red Hat Enterprise Linux to host virtual machines.

Controller nodes are responsible in order to provide endpoints for REST-based API queries to the majority of the OpenStack services. These include compute, image, identity, block, network, and data processing. The controller nodes also manage authentication and sends messaging to all the systems through a message queue and stores the state of the cloud in a database. In a production deployment, the controller nodes should be run as a highly available cluster.

Ceph Monitor nodes, which cohabitate with the controller nodes in this deployment, maintain the overall health of the Ceph cluster by keeping cluster map state including Monitor map, OSD map, Placement Group map, and CRUSH map. Monitors receive state information from other components to maintain maps and to circulate these maps to other Monitor and OSD nodes.

Converged Compute/OSD nodes are responsible for running virtual machine instances after they are launched and for holding all data generated by OpenStack. They must support hardware virtualization and provide enough CPU cycles for the instances they host. They must also have enough memory to support the requirements of the virtual machine instances they host while reserving enough memory for each Ceph OSD. Ceph OSD nodes must also provide enough usable hard drive space for the data required by the cloud.