Glossary

Application programming interface.

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.

The OpenStack core project that enables management of volumes, volume snapshots, and volume types. The project name of Block Storage is cinder.

A minimal Linux distribution designed for use as a test image on clouds such as OpenStack.

A node that runs network, volume, API, scheduler, and image services. Each service may be broken out into separate nodes for scalability or availability.

The OpenStack core project that provides compute services. The project name of the Compute service is nova.

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.

Alternative term for a cloud controller node.

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.

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.

OpenStack Networking agent that provides DHCP services for virtual networks.

See API endpoint.

A network segment typically used for instance Internet access.

Used to restrict communications between hosts and/or nodes, implemented in Compute using iptables, arptables, ip6tables, and etables.

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.

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.

An IP address, typically assigned to a router, that passes network traffic between different networks.

Feature of certain network interface drivers that combines many smaller received packets into a large packet before delivery to the kernel IP stack.

Software that arbitrates and controls VM access to the actual underlying hardware.

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.

Internet Control Message Protocol, used by network devices for control messages. For example, ping uses ICMP to test connectivity.

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.

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.

A network segment used for instance traffic tunnels between compute nodes and the network node.

A physical or virtual device that provides connectivity to another device or medium.

An OpenStack-supported hypervisor.

OpenStack Networking agent that provides layer-3 (routing) services for virtual networks.

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.

Provides a method of allocating space on mass-storage devices that is more flexible than conventional partitioning schemes.

A network segment used for administration, not accessible to the public Internet.

The software package used to provide AMQP messaging capabilities within Compute. Default package is RabbitMQ.

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.

The process of modifying IP address information while in-transit. Supported by Compute and Networking.

A method of keeping a clock for a host or node correct through communications with a trusted, accurate time source.

A core OpenStack project that provides a network connectivity abstraction layer to OpenStack Compute. The project name of Networking is neutron.

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 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.

An integrated project that orchestrates multiple cloud applications for OpenStack. The project name of Orchestration is heat.

Software component providing the actual implementation for Networking APIs, or for Compute APIs, depending on the context.

Causes the network interface to pass all traffic it receives to the host rather than passing only the frames addressed to it.

Authentication method that uses keys rather than passwords.

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.

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.

A physical or virtual network device that passes network traffic between different networks.

A set of network traffic filtering rules that are applied to a Compute instance.

Alternative term for the Identity Service catalog.

Logical subdivision of an IP network.

An integrated project that provides metering and measuring facilities for OpenStack. The project name of Telemetry is ceilometer.

A group of users, used to isolate access to Compute resources. An alternative term for a project.

OpenStack project that provides database services to applications.

In Identity Service, each user is associated with one or more tenants, and in Compute can be associated with roles, projects, or both.

An operating system instance that runs on top of a hypervisor. Multiple VMs can run at the same time on the same physical host.

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.

Open source GUI and CLI tools used for remote console access to VMs. Supported by Compute.

Provided by Compute in the form of cloudpipes, specialized instances that are used to create VPNs on a per-project basis.