Most Common Services
Nova
Primary compute engine, responsible for instance scheduling, creation and termination.
Supports:
- QEMU/KVM
- Hyper-V
- VMware ESXi
- Zen
For scaling, you would put the Nova instances in a Server Group with anti-affinity policy (to prevent ending up in the same host) and front them with a Load Balancer (Octavia).
Glance
Image service, responsible for uploading, managing, and retrieving cloud images for instances running on OpenStack. Works across variety of stores. It uses Ceph to store images
Neutron
It provides network connectivity between instances, enabling multi-VM deployments. It uses SDN technologies, including Open Virtual Network (OVN), Open vSwitch (OVS), Juniper Contrail etc.
Cinder
It is a block storage component that is responsible for provisioning, management and termination of persistent block devices. They can later be attached to instances for persistent block storage.
Swift
Swift is another storage component that provides a highly available and scalable object storage service similar to S3. It enables storing and retrieving unstructured data objects using a RESTful API for both OpenStack services and instances running on the cloud.
Keystone
An identity service, providing authentication and authorization functions for the users for multi-tenancy. It can be integrated with external systems like LDAP or Active Directory.
Less Common Services
Horizon
It is a dashboard to use with a web browser. Ships with 3 main dashboards: User dashboard, System dashboard, and Settings dashboard.
Heat
It is a service to orchestrate multiple composite cloud applications using templates
Other
| Service | Description |
|---|---|
| Mistral | Workflow management through YAML |
| Ceilometer | Telemetry for billing and components |
| Trove | Database as a service, relational & non-relational |
| Ironic | Provisioner of bare metal instead of VM |
| Octavia | Load balancer |