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Installing OpenStack for Federation with Aristotle

Steven Lee edited this page Jan 31, 2020 · 1 revision

Software Recommendations

New adopters are encouraged to use the most current supported version of OpenStack (release details). Several federation members are using Red Hat’s Openstack, but this is not a requirement to support an OpenStack cloud which can join the federation.

Hardware Recommendations

Openstack Management and Compute

Controller Cluster

For high availability, a 3 controller node cluster is recommended. All Openstack components except for nova compute run on all 3 nodes of the controller cluster. Cinder (volume) runs in A/P mode whereas all other components run in A/A mode.

Each controller node needs two ethernet interfaces: one for internal/management network and one for public/provider network. It also needs enough disk space for Horizon to save uploaded images temporarily before they are uploaded to Glance.


Compute nodes run the cloud instances so hardware configurations depend on the specs of the instance flavors and CPU/RAM oversubscription ratios.

Each compute node needs two ethernet interfaces: one for internal/management network and one for public/provider network.

Storage: Ceph

A Ceph cluster provides storage for:

  • volumes,
  • images,
  • boot volumes for VMs, and
  • object storage.


A minimum of 3 monitors on their own physical servers per cluster is needed. If the cluster has more than 400 OSDs, use 5 monitors. The monitors need to establish a quorum to update maps. Each monitor node should have:

  • 2 GB of RAM
  • SSD or fast SAS drives in RAID5.

OSD Nodes

A minimum of 3 OSD nodes is required for high availability and fault tolerance. Objects are distributed across OSDs according to CRUSH rules. More OSD nodes means more bandwidth to data and fault tolerance.

For good block storage (volumes, images, VM boot volumes) performance, each OSD node should have at least:

  • 1 GHz of hyperthreaded CPU core per OSD
  • 1 GB of RAM per raw TB hosted.
  • 2 10 Gb/s NICs on separate PCI cards: 1 NIC on the public network for client-facing traffic; 1 NIC on the cluster network (replication and recovery operations)
  • (optional) SSD for hosting OSD write journals:
    • SATA SSD: 6 OSD write journals/SSD.
    • NVMe SSD: 12 OSD write journals/SSD.

Sample OSD Node Configuration

The Ceph cluster at Cornell University Center for Advanced Computing has 12 of the following OSD nodes:

  • Dell PowerEdge R730 Server
    • Dual Intel Xeon E5-2630 v3 CPUs (16 cores/32 threads total)
    • 128 GB RAM
    • 2 mirrored SAS drives for server OS.
    • 12 OSDs: Each OSD is hosted on a 8 TB 7200 RPM SAS drive.
    • 2 200 GB SATA SSDs. Each SSD hosts 6 OSD write journals.
    • 2 10 Gb/s NICs: 1 on motherboard; 1 on PCI card.

RADOS Gateway

For maximum bandwidth, the server should have many CPU cores/threads as possible. For high availability, install multiple RADOS Gateway servers behind a load balancer. Swift/S3 API are RESTful.