swarm集群部署
简介部署swarm搭建私有仓库部署集群部署serviceservice伸缩实现 Failover访问 service
简介
Swarm的特性： 1.工作节点的注册和发现 2.管理节点收集集群中所有的信息 3.管理节点支持HA 4.管理节点能感知集群的变化，在节点挂掉后重新调度上面的container 5.提供filter和scheduler的调度策略调度集群里的容器
Swarm概念 swarm：是一组docker引擎的集群 node：是单个docker引擎的实例，可以在一个物理机上也可以在多个 application：是应用 manager node：部署应用的时候会有一个manager node节点 Worker nodes：对应的就是Worker nodes service：然后service是一堆被workder执行的任务 replicated services：是负载均衡节点 global services：则是全局的，在所有节点上都会执行的一个服务 task：一个task就是一个docker的容器，是Swarm的工作单元
部署swarm
环境： swarm 192.168.1.10 node1 192.168.1.20 node2 192.168.1.30
搭建私有仓库
docker pull registry:2
mkdir -p /opt/data/registry
docker run -dit -p 5000:5000 --restart always -v /opt/data/registry/:/var/lib/registry --name registry registry:2
vim /usr/lib/systemd/system/docker.service ##添加--insecure-registry 192.168.1.10:5000
ExecStart=/usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock --insecure-registry 192.168.1.10:5000
##其余两台worker同样添加
##下载httpd打包
docker pull httpd
docker tag httpd:latest 192.168.1.10:5000/httpd
docker push 192.168.1.10:5000/httpd
curl 192.168.1.10:5000/v2/_catalog
{"repositories":["httpd","visualizer"]}
部署集群
vim /etc/hosts
192.168.1.20 node1
192.168.1.30 node2
ssh-keygen ##一直回车
ssh-copy-id node1
ssh-copy-id node2
##开启防火墙相应端口
firewall-cmd --add-port=2377/tcp --permanent
firewall-cmd --add-port=7946/tcp --permanent
firewall-cmd --add-port=7946/udp --permanent
firewall-cmd --add-port=4789/udp --permanent
firewall-cmd --add-port=4789/tcp --permanent
firewall-cmd --reload
初始化
docker swarm init --advertise-addr 192.168.1.10 ##会有提示如何加入集群
docker swarm join-token manager ##查看加入集群命令
docker node ls
ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS ENGINE VERSION
mil1gpiau7ujhfjgnvp5hdzc7 * swarm Ready Active Leader 19.03.12
##node1与node2 ##加入集群
docker swarm join --token SWMTKN-1-15skd1ufc98589qgpxwzksft7e4ml4bxrkjj2j0lkqooa4pe1p-88tzyad1zi5i77lveqbxmqstn 192.168.1.10:2377
##swarm
docker node ls
docker node ls
ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS ENGINE VERSION
n9okoh4p9gihvr80u9hiwoetu node1 Ready Active 19.03.12
nvnjwoixsql85aveph6247lwe node2 Ready Active 19.03.12
mil1gpiau7ujhfjgnvp5hdzc7 * swarm Ready Active Leader 19.03.12
下载可视化工具
docker pull dockersamples/visualizer
docker run -dit -p 8888:8080 -e HOST=192.368.1.10 -v /var/run/docker.sock:/var/run/docker.sock 192.168.1.10:5000/visualizer
##访问 ip：8888
部署service
##swarm
docker service create --name web_server 192.168.1.10:5000/httpd
docker service ls
ID NAME MODE REPLICAS IMAGE PORTS
n164bmq4u7uc web_server replicated 3/3 192.168.1.10:5000/httpd:latest
REPLICAS 显示当前副本信息，0/1 的意思是 web_server 这个 service 期望的容器副本数量为 1，目前已经启动的副本数量为 0。也就是当前 service 还没有部署完成。命令 docker service ps 可以查看 service 每个副本的状态。
docker service ps web_server
ID NAME IMAGE NODE DESIRED STATE CURRENT STATE ERROR PORTS
8amf6th0zfh9 web_server.1 192.168.1.10:5000/httpd:latest node2 Running Running 15 seconds ago
service伸缩
docker service scale web_server=5
web_server scaled to 5
overall progress: 5 out of 5 tasks
1/5: running [==================================================>]
2/5: running [==================================================>]
3/5: running [==================================================>]
4/5: running [==================================================>]
5/5: running [==================================================>]
verify: Service converged
docker service ps web_server
ID NAME IMAGE NODE DESIRED STATE CURRENT STATE ERROR PORTS
8amf6th0zfh9 web_server.1 192.168.1.10:5000/httpd:latest node2 Running Running 3 minutes ago
rog6rlrpke84 web_server.2 192.168.1.10:5000/httpd:latest swarm Running Running 18 seconds ago
vt9goq7efi0v web_server.3 192.168.1.10:5000/httpd:latest node2 Running Running 18 seconds ago
nlc7x2st1ay8 web_server.4 192.168.1.10:5000/httpd:latest node1 Running Running 18 seconds ago
g44z1ksntkk8 web_server.5 192.168.1.10:5000/httpd:latest swarm Running Running 18 seconds ago
实现 Failover
##关闭node1
poweroff
##还是5个服务
访问 service
在创建service时添加 --publish-add 暴露端口如：
docker service create --publish 8080:80 192.168.1.10:5000/httpd
对于已经创建的service使用更新的命令
docker service update --publish-add 8080:80 web_server
验证
curl 192.168.1.10:8080
It works!
curl 192.168.1.20:8080
It works!
curl 192.168.1.30:8080
It works!
