Chapter 3. Hardware Recommendations

This reference architecture focuses on:

  • Providing configuration instruction details
  • Validating the interoperability of Red Hat OpenStack Platform Nova Compute instances and Red Hat Ceph Storage on the same physical servers.
  • Providing automated methods to apply resource isolation to avoid contention between Nova Compute and Ceph OSD services.

Red Hat’s experience with early hyper-converged adopters reflect a wide variety of hardware configurations. Baseline hardware performance and sizing recommendations for non-hyper-converged Ceph clusters can be found in the Hardware Selection Guide for Ceph.

Additional considerations for hyper-converged Red Hat OpenStack Platform with Red Hat Ceph Storage server nodes include:

  • Network: the recommendation is to configure 2x 10GbE NICs for Ceph. Additional NICs are recommended to meet Nova VM workload networking requirements that include bonding of NICs and trunking of VLANs.
  • RAM: the recommendation is to configure 2x RAM needed by the resident Nova VM workloads.
  • OSD Media: the recommendation is to configure 7,200 RPM enterprise HDDs for general-purpose workloads or NVMe SSDs for IOPS-intensive workloads. For workloads requiring large amounts of storage capacity, it may be better to configure separate storage and compute server pools (non hyper-converged).
  • Journal Media: the recommendation is to configure SAS/SATA SSDs for general-purpose workloads or NVMe SSDs for IOPS-intensive workloads.
  • CPU: the recommendation is to configure a minimum dual-socket 16-core CPUs for servers with NVMe storage media, or dual-socket 10-core CPUs for servers with SAS/SATA SSDs.

Details of the hardware configuration for this reference architecture can be found in Appendix: Environment Details.

3.1. Required Servers

The minimum infrastructure requires at least six bare metal servers and either a seventh bare metal server or virtual machine hosted separately, not hosted on the six bare metal servers. These servers should be deployed in the following roles:

  • 1 Red Hat OpenStack Platform director server (can be virtualized for small deployments)
  • 3 Cloud Controllers/Ceph Monitors (Controller/Mon nodes)
  • 3 Compute Hypervisors/Ceph storage servers (Compute/OSD nodes)

As part of this reference architecture, a fourth Compute/Ceph storage node is added to demonstrate scaling of an infrastructure.


Additional Compute/Ceph storage nodes may be initially deployed or added later. However, for deployments spanning more than one datacenter rack (42 nodes), Red Hat recommends the use of standalone storage and compute, and not a hyper-converged approach.