Docker Swarm是Docker的本机集群。 它允许您使用全套Docker工具创建和访问Docker主机池。 因为Docker Swarm提供了标准的Docker API，所以任何已经与Docker守护程序通信的工具都可以使用Swarm透明地扩展到多个主机。

docker swarm 提升从节点为副主节点 docker swarm consul_分布式

Docker Swarm具有一个Manager ，一个预定义的Docker Host，并且是所有管理的单点。 Swarm Manager在整个集群上编排和调度容器，并且可以在High Availability中进行配置。 容器部署在作为其他Docker主机的节点上。

docker swarm 提升从节点为副主节点 docker swarm consul_分布式_02

Swarm与托管的发现服务进行对话，该服务维护您群集中的IP列表。 对于开发而言，它易于使用，托管在Docker Hub上的默认发现服务。 安装和创建Docker Swarm中提供了完整的说明。 该博客将展示如何使用Consul设置Docker Swarm Cluster。

让我们开始吧！

创建领事发现服务

docker-machine create -d=virtualbox consul-machine
Running pre-create checks...
Creating machine...
Waiting for machine to be running, this may take a few minutes...
Machine is running, waiting for SSH to be available...
Detecting operating system of created instance...
Provisioning created instance...
Copying certs to the local machine directory...
Copying certs to the remote machine...
Setting Docker configuration on the remote daemon...
To see how to connect Docker to this machine, run: docker-machine env consul-machine
eval $(docker-machine env consul-machine)
myconsul:
  image: progrium/consul
  restart: always
  hostname: consul
  ports:
    - 8500:8500
  command: "-server -bootstrap"

该文件也可以在/arun-gupta/docker-images/tree/master/consul中找到 。 服务启动为： 

docker-compose up -d
Pulling myconsul (progrium/consul:latest)...
latest: Pulling from progrium/consul
3b4d28ce80e4: Pull complete
e5ab901dcf2d: Pull complete
30ad296c0ea0: Pull complete
3dba40dec256: Pull complete
f2ef4387b95e: Pull complete
53bc8dcc4791: Pull complete
75ed0b50ba1d: Pull complete
17c3a7ed5521: Pull complete
8aca9e0ecf68: Pull complete
4d1828359d36: Pull complete
46ed7df7f742: Pull complete
b5e8ce623ef8: Pull complete
049dca6ef253: Pull complete
bdb608bc4555: Pull complete
8b3d489cfb73: Pull complete
c74500bbce24: Pull complete
9f3e605442f6: Pull complete
d9125e9e799b: Pull complete
Digest: sha256:8cc8023462905929df9a79ff67ee435a36848ce7a10f18d6d0faba9306b97274
Status: Downloaded newer image for progrium/consul:latest
Creating consul_myconsul_1

启动的容器可以验证为： 

docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
f05d8dd11e7f progrium/consul "/bin/start -server -" 30 seconds ago Up 29 seconds 53/tcp, 53/udp, 8300-8302/tcp, 8400/tcp, 0.0.0.0:8500->8500/tcp, 8301-8302/udp consul_myconsul_1

使用Consul创建Docker Swarm集群

Swarm与Machine完全集成在一起，因此是最简单的入门方法。 

docker-machine create -d virtualbox --swarm --swarm-master --swarm-discovery="consul://$(docker-machine ip consul-machine):8500" --engine-opt="cluster-store=consul://$(docker-machine ip consul-machine):8500" --engine-opt="cluster-advertise=eth1:2376" swarm-master
Running pre-create checks...
Creating machine...
Waiting for machine to be running, this may take a few minutes...
Machine is running, waiting for SSH to be available...
Detecting operating system of created instance...
Provisioning created instance...
Copying certs to the local machine directory...
Copying certs to the remote machine...
Setting Docker configuration on the remote daemon...
Configuring swarm...
To see how to connect Docker to this machine, run: docker-machine env swarm-master

在此处查看三个选项：

  • --swarm-discovery定义发现服务的地址
  • --cluster-advertise在网络上播发计算机
  • --cluster-store指定集群的分布式k / v存储后端

此外， --swarm将机器配置为Swarm， --swarm-master将创建的机器配置为Swarm主机。 

eval "$(docker-machine env swarm-master)"
docker info

这将输出显示为： 

docker info
Containers: 2
Images: 8
Server Version: 1.9.0
Storage Driver: aufs
 Root Dir: /mnt/sda1/var/lib/docker/aufs
 Backing Filesystem: tmpfs
 Dirs: 12
 Dirperm1 Supported: true
Execution Driver: native-0.2
Logging Driver: json-file
Kernel Version: 4.1.12-boot2docker
Operating System: Boot2Docker 1.9.0 (TCL 6.4); master : 16e4a2a - Tue Nov  3 19:49:22 UTC 2015
CPUs: 1
Total Memory: 996.2 MiB
Name: swarm-master
ID: 2EDA:WPOD:YVWO:GGLZ:ZUHY:WCBU:ZERW:OWBE:6MPQ:IPXN:BS2V:QCSI
Debug mode (server): true
 File Descriptors: 30
 Goroutines: 67
 System Time: 2015-11-29T02:08:10.636829121Z
 EventsListeners: 1
 Init SHA1: 
 Init Path: /usr/local/bin/docker
 Docker Root Dir: /mnt/sda1/var/lib/docker
Username: arungupta
Registry: https:///v1/
Labels:
 provider=virtualbox
Cluster store: consul://192.168.99.109:8500
Cluster advertise: 192.168.99.111:2376
docker-machine create -d virtualbox --swarm --swarm-discovery="consul://$(docker-machine ip consul-machine):8500" --engine-opt="cluster-store=consul://$(docker-machine ip consul-machine):8500" --engine-opt="cluster-advertise=eth1:2376" swarm-node-01
Running pre-create checks...
Creating machine...
Waiting for machine to be running, this may take a few minutes...
Machine is running, waiting for SSH to be available...
Detecting operating system of created instance...
Provisioning created instance...
Copying certs to the local machine directory...
Copying certs to the remote machine...
Setting Docker configuration on the remote daemon...
Configuring swarm...
To see how to connect Docker to this machine, run: docker-machine env swarm-node-01

机器使用--swarm-discovery与发现服务--swarm-discovery 。 

docker-machine create -d virtualbox --swarm --swarm-discovery="consul://$(docker-machine ip consul-machine):8500" --engine-opt="cluster-store=consul://$(docker-machine ip consul-machine):8500" --engine-opt="cluster-advertise=eth1:2376" swarm-node-02
Running pre-create checks...
Creating machine...
Waiting for machine to be running, this may take a few minutes...
Machine is running, waiting for SSH to be available...
Detecting operating system of created instance...
Provisioning created instance...
Copying certs to the local machine directory...
Copying certs to the remote machine...
Setting Docker configuration on the remote daemon...
Configuring swarm...
To see how to connect Docker to this machine, run: docker-machine env swarm-node-02
docker-machine ls 
NAME             ACTIVE   DRIVER       STATE     URL                         SWARM
consul-machine   -        virtualbox   Running   tcp://192.168.99.109:2376   
default          -        virtualbox   Running   tcp://192.168.99.100:2376   
swarm-master     *        virtualbox   Running   tcp://192.168.99.111:2376   swarm-master (master)
swarm-node-01    -        virtualbox   Running   tcp://192.168.99.112:2376   swarm-master
swarm-node-02    -        virtualbox   Running   tcp://192.168.99.113:2376   swarm-master

属于群集的计算机在“群集”列中具有群集的名称，否则为空白。 例如，“ default ”和“ consul-machine ”是独立计算机，其中所有其他计算机都是“ swarm-master ”集群的一部分。 Swarm主机也由SWARM列中的（主机）标识。 

eval "$(docker-machine env --swarm swarm-master)"
docker info

这里的主要区别是--swarm当查找有关Swarm集群的信息而不是单个Machine时。

输出显示为： 

docker info
Containers: 4
Images: 3
Role: primary
Strategy: spread
Filters: health, port, dependency, affinity, constraint
Nodes: 3
 swarm-master: 192.168.99.111:2376
  └ Containers: 2
  └ Reserved CPUs: 0 / 1
  └ Reserved Memory: 0 B / 1.021 GiB
  └ Labels: executiondriver=native-0.2, kernelversion=4.1.12-boot2docker, operatingsystem=Boot2Docker 1.9.0 (TCL 6.4); master : 16e4a2a - Tue Nov  3 19:49:22 UTC 2015, provider=virtualbox, storagedriver=aufs
 swarm-node-01: 192.168.99.112:2376
  └ Containers: 1
  └ Reserved CPUs: 0 / 1
  └ Reserved Memory: 0 B / 1.021 GiB
  └ Labels: executiondriver=native-0.2, kernelversion=4.1.12-boot2docker, operatingsystem=Boot2Docker 1.9.0 (TCL 6.4); master : 16e4a2a - Tue Nov  3 19:49:22 UTC 2015, provider=virtualbox, storagedriver=aufs
 swarm-node-02: 192.168.99.113:2376
  └ Containers: 1
  └ Reserved CPUs: 0 / 1
  └ Reserved Memory: 0 B / 1.021 GiB
  └ Labels: executiondriver=native-0.2, kernelversion=4.1.12-boot2docker, operatingsystem=Boot2Docker 1.9.0 (TCL 6.4); master : 16e4a2a - Tue Nov  3 19:49:22 UTC 2015, provider=virtualbox, storagedriver=aufs
CPUs: 3
Total Memory: 3.064 GiB
Name: 10edc606d097

有3个节点-一个Swarm主节点和2个Swarm _worker_节点。 此群集中总共有4个容器在运行–主节点和每个节点上有一个Swarm代理，主节点上还有一个额外的swarm-agent-master。 可以通过连接到主数据库并列出所有容器来验证这一点。 

docker run swarm list consul://$(docker-machine ip consul-machine):8500
192.168.99.111:2376
192.168.99.112:2376
192.168.99.113:2376
  1. 随后的博客将解释如何将应用程序部署到此Docker Swarm集群。
    请享用！