Merge pull request #25817 from sfsmithcha/update_glossary

add swarm mode terms to the glossary
(cherry picked from commit 027e7be348)

Signed-off-by: Misty Stanley-Jones <misty@docker.com>
This commit is contained in:
Sebastiaan van Stijn 2016-09-13 12:08:32 +02:00 committed by Misty Stanley-Jones
parent c6e7fececb
commit 7c8dc9e6d5

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@ -19,7 +19,7 @@ aufs (advanced multi layered unification filesystem) is a Linux [filesystem](#fi
Docker supports as a storage backend. It implements the
[union mount](http://en.wikipedia.org/wiki/Union_mount) for Linux file systems.
## Base image
## base image
An image that has no parent is a **base image**.
@ -153,6 +153,16 @@ installs Docker on them, then configures the Docker client to talk to them.
*Also known as : docker-machine*
## node
A [node](../swarm/how-swarm-mode-works/nodes.md) is a physical or virtual
machine running an instance of the Docker Engine in swarm mode.
**Manager nodes** perform swarm management and orchestration duties. By default
manager nodes are also worker nodes.
**Worker nodes** execute tasks.
## overlay network driver
Overlay network driver provides out of the box multi-host network connectivity
@ -181,15 +191,54 @@ labeled using [tags](#tag).
Here is an example of the shared [nginx repository](https://hub.docker.com/_/nginx/)
and its [tags](https://hub.docker.com/r/library/nginx/tags/)
## service
A [service](../swarm/how-swarm-mode-works/services.md) is the definition of how
you want to run your application containers in a swarm. At the most basic level
a service defines which container image to run in the swarm and which commands
to run in the container. For orchestration purposes, the service defines the
"desired state", meaning how many containers to run as tasks and constraints for
deploying the containers.
Frequently a service is a microservice within the context of some larger
application. Examples of services might include an HTTP server, a database, or
any other type of executable program that you wish to run in a distributed
environment.
## service discovery
Swarm mode [service discovery](../swarm/networking.md) is a DNS component
internal to the swarm that automatically assigns each service on an overlay
network in the swarm a VIP and DNS entry. Containers on the network share DNS
mappings for the service via gossip so any container on the network can access
the service via its service name.
You dont need to expose service-specific ports to make the service available to
other services on the same overlay network. The swarms internal load balancer
automatically distributes requests to the service VIP among the active tasks.
## swarm
A [swarm](../swarm/index.md) is a cluster of one or more Docker Engines running in [swarm mode](#swarm-mode).
## Swarm
[Swarm](https://github.com/docker/swarm) is a native clustering tool for Docker.
Swarm pools together several Docker hosts and exposes them as a single virtual
Docker host. It serves the standard Docker API, so any tool that already works
with Docker can now transparently scale up to multiple hosts.
Do not confuse [Docker Swarm](https://github.com/docker/swarm) with the [swarm mode](#swarm-mode) features in Docker Engine.
Docker Swarm is the name of a standalone native clustering tool for Docker.
Docker Swarm pools together several Docker hosts and exposes them as a single
virtual Docker host. It serves the standard Docker API, so any tool that already
works with Docker can now transparently scale up to multiple hosts.
*Also known as : docker-swarm*
## swarm mode
[Swarm mode](../swarm/index.md) refers to cluster management and orchestration
features embedded in Docker Engine. When you initialize a new swarm (cluster) or
join nodes to a swarm, the Docker Engine runs in swarm mode.
## tag
A tag is a label applied to a Docker image in a [repository](#repository).
@ -197,6 +246,18 @@ tags are how various images in a repository are distinguished from each other.
*Note : This label is not related to the key=value labels set for docker daemon*
## task
A [task](../swarm/how-swarm-mode-works/services.md#tasks-and-scheduling) is the
atomic unit of scheduling within a swarm. A task carries a Docker container and
the commands to run inside the container. Manager nodes assign tasks to worker
nodes according to the number of replicas set in the service scale.
The diagram below illustrates the relationship of services to tasks and
containers.
![services diagram](../swarm/images/services-diagram.png)
## Toolbox
Docker Toolbox is the installer for Mac and Windows users.
@ -209,13 +270,13 @@ very lightweight and fast. Docker uses union file systems to provide the buildin
blocks for containers.
## Virtual Machine
## virtual machine
A Virtual Machine is a program that emulates a complete computer and imitates dedicated hardware.
A virtual machine is a program that emulates a complete computer and imitates dedicated hardware.
It shares physical hardware resources with other users but isolates the operating system. The
end user has the same experience on a Virtual Machine as they would have on dedicated hardware.
Compared to to containers, a Virtual Machine is heavier to run, provides more isolation,
Compared to to containers, a virtual machine is heavier to run, provides more isolation,
gets its own set of resources and does minimal sharing.
*Also known as : VM*