- API
Application programming interface.
- API endpoint
The daemon, worker, or service that a client communicates with to access an API. API endpoints can provide any number of services, such as authentication, sales data, performance metrics, Compute VM commands, census data, and so on.
- Block Storage
The OpenStack core project that enables management of volumes, volume snapshots, and volume types. The project name of Block Storage is cinder.
- CirrOS
A minimal Linux distribution designed for use as a test image on clouds such as OpenStack.
- cloud controller node
A node that runs network, volume, API, scheduler, and image services. Each service may be broken out into separate nodes for scalability or availability.
- Compute
The OpenStack core project that provides compute services. The project name of the Compute service is nova.
- compute node
A node that runs the
nova-compute
daemon which manages VM instances that provide a wide range of services such as a web applications and analytics.- controller node
Alternative term for a cloud controller node.
- Database Service
An integrated project that provide scalable and reliable Cloud Database-as-a-Service functionality for both relational and non-relational database engines. The project name of Database Service is trove.
- DHCP
Dynamic Host Configuration Protocol. A network protocol that configures devices that are connected to a network so that they can communicate on that network by using the Internet Protocol (IP). The protocol is implemented in a client-server model where DHCP clients request configuration data such as, an IP address, a default route, and one or more DNS server addresses from a DHCP server.
- DHCP agent
OpenStack Networking agent that provides DHCP services for virtual networks.
- endpoint
See API endpoint.
- external network
A network segment typically used for instance Internet access.
- firewall
Used to restrict communications between hosts and/or nodes, implemented in Compute using iptables, arptables, ip6tables, and etables.
- flat network
The Network Controller provides virtual networks to enable compute servers to interact with each other and with the public network. All machines must have a public and private network interface. A flat network is a private network interface, which is controlled by the flat_interface option with flat managers.
- floating IP address
An IP address that a project can associate with a VM so that the instance has the same public IP address each time that it boots. You create a pool of floating IP addresses and assign them to instances as they are launched to maintain a consistent IP address for maintaining DNS assignment.
- gateway
An IP address, typically assigned to a router, that passes network traffic between different networks.
- Generic Receive Offload (GRO)
Feature of certain network interface drivers that combines many smaller received packets into a large packet before delivery to the kernel IP stack.
- hypervisor
Software that arbitrates and controls VM access to the actual underlying hardware.
- IaaS
Infrastructure-as-a-Service. IaaS is a provisioning model in which an organization outsources physical components of a data center such as storage, hardware, servers and networking components. A service provider owns the equipment and is responsible for housing, operating and maintaining it. The client typically pays on a per-use basis. IaaS is a model for providing cloud services.
- Icehouse
Project name for the ninth release of OpenStack.
- ICMP
Internet Control Message Protocol, used by network devices for control messages. For example, ping uses ICMP to test connectivity.
- Identity Service
The OpenStack core project that provides a central directory of users mapped to the OpenStack services they can access. It also registers endpoints for OpenStack services. It acts as a common authentication system. The project name of the Identity Service is keystone.
- Image Service
An OpenStack core project that provides discovery, registration, and delivery services for disk and server images. The project name of the Image Service is glance.
- instance tunnels network
A network segment used for instance traffic tunnels between compute nodes and the network node.
- interface
A physical or virtual device that provides connectivity to another device or medium.
- kernel-based VM (KVM)
An OpenStack-supported hypervisor.
- Layer-3 (L3) agent
OpenStack Networking agent that provides layer-3 (routing) services for virtual networks.
- load balancer
A load balancer is a logical device that belongs to a cloud account. It is used to distribute workloads between multiple back-end systems or services, based on the criteria defined as part of its configuration.
- Logical Volume Manager (LVM)
Provides a method of allocating space on mass-storage devices that is more flexible than conventional partitioning schemes.
- management network
A network segment used for administration, not accessible to the public Internet.
- message broker
The software package used to provide AMQP messaging capabilities within Compute. Default package is RabbitMQ.
- multi-host
High-availability mode for legacy (nova) networking. Each compute node handles NAT and DHCP and acts as a gateway for all of the VMs on it. A networking failure on one compute node doesn't affect VMs on other compute nodes.
- Network Address Translation (NAT)
The process of modifying IP address information while in-transit. Supported by Compute and Networking.
- Network Time Protocol (NTP)
A method of keeping a clock for a host or node correct through communications with a trusted, accurate time source.
- Networking
A core OpenStack project that provides a network connectivity abstraction layer to OpenStack Compute. The project name of Networking is neutron.
- Object Storage
The OpenStack core project that provides eventually consistent and redundant storage and retrieval of fixed digital content. The project name of OpenStack Object Storage is swift.
- OpenStack
OpenStack is a cloud operating system that controls large pools of compute, storage, and networking resources throughout a data center, all managed through a dashboard that gives administrators control while empowering their users to provision resources through a web interface. OpenStack is an open source project licensed under the Apache License 2.0.
- Orchestration
An integrated project that orchestrates multiple cloud applications for OpenStack. The project name of Orchestration is heat.
- plug-in
Software component providing the actual implementation for Networking APIs, or for Compute APIs, depending on the context.
- promiscuous mode
Causes the network interface to pass all traffic it receives to the host rather than passing only the frames addressed to it.
- public key authentication
Authentication method that uses keys rather than passwords.
- RESTful
A kind of web service API that uses REST, or Representational State Transfer. REST is the style of architecture for hypermedia systems that is used for the World Wide Web.
- role
A personality that a user assumes that enables them to perform a specific set of operations. A role includes a set of rights and privileges. A user assuming that role inherits those rights and privileges.
- router
A physical or virtual network device that passes network traffic between different networks.
- security group
A set of network traffic filtering rules that are applied to a Compute instance.
- service catalog
Alternative term for the Identity Service catalog.
- subnet
Logical subdivision of an IP network.
- Telemetry
An integrated project that provides metering and measuring facilities for OpenStack. The project name of Telemetry is ceilometer.
- tenant
A group of users, used to isolate access to Compute resources. An alternative term for a project.
- trove
OpenStack project that provides database services to applications.
- user
In Identity Service, each user is associated with one or more tenants, and in Compute can be associated with roles, projects, or both.
- virtual machine (VM)
An operating system instance that runs on top of a hypervisor. Multiple VMs can run at the same time on the same physical host.
- virtual networking
A generic term for virtualization of network functions such as switching, routing, load balancing, and security using a combination of VMs and overlays on physical network infrastructure.
- Virtual Network Computing (VNC)
Open source GUI and CLI tools used for remote console access to VMs. Supported by Compute.
- virtual private network (VPN)
Provided by Compute in the form of cloudpipes, specialized instances that are used to create VPNs on a per-project basis.