Docker Swarm集群搭建与测试
Docker Swarm
文档
https://docs.docker.com/engine/swarm/
参考
https://qiita.com/Brutus/items/b3dfe5957294caa82669
https://docs.docker.jp/swarm/overview.html
架构示意
Manager可以管理集群，也可以运行容器
worker只能运行容器
搭建
docker环境搭建
OS设置
# 关闭SELinux，firewalld
# 网络设置
[root@vm1 ~]# ip -br a | grep 0s8 | awk '{print $3}'
192.168.50.100/24
[root@vm2 ~]# ip -br a | grep 0s8 | awk '{print $3}'
192.168.50.120/24
安装docker，compose
# docker
[root@vm1 ~]# cat install-docker.sh
yum remove docker* -y
rm -rf /var/lib/docker
yum -y install wget
wget -O /etc/yum.repos.d/docker-ce.repo https://download.docker.com/linux/centos/docker-ce.repo
yum install docker-ce docker-ce-cli containerd.io -y
docker --version
systemctl enable docker --now
docker run hello-world
[root@vm1 ~]# bash install-docker.sh
# 安装docker-compose（任意）
[root@vm1 ~]# curl -L "https://github.com/docker/compose/releases/download/1.29.2/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
[root@vm1 ~]# chmod +x /usr/local/bin/docker-compose
[root@vm1 ~]# docker -v
Docker version 20.10.12, build e91ed57
[root@vm1 ~]# docker-compose -v
docker-compose version 1.29.2, build 5becea4c
[root@vm2 ~]# docker -v
Docker version 20.10.12, build e91ed57
[root@vm2 ~]# docker-compose -v
docker-compose version 1.29.2, build 5becea4c
docker0网络（不用修改）
[root@vm1 ~]# docker network inspect bridge -f "{{.IPAM.Config}}"
[{192.168.80.0/24 192.168.80.1 map[]}]
[root@vm2 ~]# docker network inspect bridge -f "{{.IPAM.Config}}"
[{192.168.90.0/24 192.168.90.1 map[]}]
Swarm集群搭建
初始化#1（manager）
[root@vm1 ~]# docker swarm init --advertise-addr 192.168.50.100
Swarm initialized: current node (kdcrkd6sqteevq9jgy70fd0h0) is now a manager.
To add a worker to this swarm, run the following command:
docker swarm join --token SWMTKN-1-0h1lwim8eh8ygwmh9mg3chuep8lf3dh0z8iv79v3km7itl28ww-4yt8thj4v7a2sj45iab6v8qqj 192.168.50.100:2377
To add a manager to this swarm, run 'docker swarm join-token manager' and follow the instructions.
# 亦可手动获取令牌token
[root@vm1 ~]# docker swarm join-token worker
To add a worker to this swarm, run the following command:
docker swarm join --token SWMTKN-1-0h1lwim8eh8ygwmh9mg3chuep8lf3dh0z8iv79v3km7itl28ww-4yt8thj4v7a2sj45iab6v8qqj 192.168.50.100:2377
# 查看集群节点
[root@vm1 ~]# docker node ls
ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS ENGINE VERSION
kdcrkd6sqteevq9jgy70fd0h0 * vm1 Ready Active Leader 20.10.12
worker加入集群
[root@vm2 ~]# docker swarm join --token SWMTKN-1-0h1lwim8eh8ygwmh9mg3chuep8lf3dh0z8iv79v3km7itl28ww-4yt8thj4v7a2sj45iab6v8qqj 192.168.50.100:2377
This node joined a swarm as a worker.
查看集群节点
[root@vm2 ~]# docker node ls
Error response from daemon: This node is not a swarm manager. Worker nodes can't be used to view or modify cluster state. Please run this command on a manager node or promote the current node to a manager.
ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS ENGINE VERSION
kdcrkd6sqteevq9jgy70fd0h0 * vm1 Ready Active Leader 20.10.12
4hh92oj2meotbi0etnje15bzq vm2 Ready Active 20.10.12
添加label
dns主机别名？
[root@vm1 ~]# docker node update --label-add name=swarm-master-1 vm1
vm1
[root@vm1 ~]# docker node update --label-add name=swarm-master-2 vm2
vm2
[root@vm1 ~]# docker node ls
ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS ENGINE VERSION
kdcrkd6sqteevq9jgy70fd0h0 * vm1 Ready Active Leader 20.10.12
4hh92oj2meotbi0etnje15bzq vm2 Ready Active 20.10.12
查看label
[root@vm1 ~]# docker node inspect vm1 -f "{{.Spec.Labels}}"
map[name:swarm-master-1]
[root@vm1 ~]# docker node inspect vm2 -f "{{.Spec.Labels}}"
map[HOSTNAME:master-2 name:master-2]
这个label貌似没用？
[root@vm1 ~]# docker node update --help
Usage: docker node update [OPTIONS] NODE
Update a node
Options:
--availability string Availability of the node ("active"|"pause"|"drain")
--label-add list Add or update a node label (key=value)
--label-rm list Remove a node label if exists
--role string Role of the node ("worker"|"manager")
[root@vm1 ~]# docker node update --label-add name=master-2 vm2
vm2
[root@vm1 ~]# echo $?
0
[root@vm1 ~]#
[root@vm1 ~]# docker node ls
ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS ENGINE VERSION
kdcrkd6sqteevq9jgy70fd0h0 * vm1 Ready Active Leader 20.10.12
4hh92oj2meotbi0etnje15bzq vm2 Ready Active 20.10.12
[root@vm1 ~]# docker node promote master-2
Error: No such node: master-2
[root@vm1 ~]# docker node promote master-2
Error: No such node: master-2
[root@vm1 ~]# docker node update --label-add HOSTNAME=master-2 vm2
vm2
[root@vm1 ~]# docker node ls
ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS ENGINE VERSION
kdcrkd6sqteevq9jgy70fd0h0 * vm1 Ready Active Leader 20.10.12
4hh92oj2meotbi0etnje15bzq vm2 Ready Active 20.10.12
[root@vm1 ~]# docker node promote master-2
Error: No such node: master-2
提升worker为master
[root@vm1 ~]# docker node ls
ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS ENGINE VERSION
kdcrkd6sqteevq9jgy70fd0h0 * vm1 Ready Active Leader 20.10.12
4hh92oj2meotbi0etnje15bzq vm2 Ready Active Reachable 20.10.12
2号可以查看集群情况了
[root@vm2 ~]# docker node ls
ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS ENGINE VERSION
kdcrkd6sqteevq9jgy70fd0h0 vm1 Ready Active Leader 20.10.12
4hh92oj2meotbi0etnje15bzq * vm2 Ready Active Reachable 20.10.12
查看节点的信息
[root@vm1 ~]# docker node inspect vm2 -f "{{.Spec.Labels}}"
map[HOSTNAME:master-2 name:master-2]
[root@vm1 ~]# docker node inspect vm2
创建网络
指定为overlay
[root@vm1 ~]# docker network create -d overlay --subnet=192.168.82.0/24 --gateway=192.168.82.1 --attachable swarm-net
xywzrf7ftwenaxbu0zmewh183
查看
[root@vm1 ~]# docker network inspect swarm-net -f "{{.IPAM}}"
{default map[] [{192.168.82.0/24 192.168.82.1 map[]}]}
创建service并验证
创建
[root@vm1 ~]# docker service create --replicas 3 -p 10080:80 --network swarm-net --name nginx-cluster nginx
r4v6w094yxl370bynyzghh37a
overall progress: 3 out of 3 tasks
1/3: running [==================================================>]
2/3: running [==================================================>]
3/3: running [==================================================>]
verify: Service converged
[root@vm1 ~]#
查看
[root@vm1 ~]# docker service ls
ID NAME MODE REPLICAS IMAGE PORTS
r4v6w094yxl3 nginx-cluster replicated 3/3 nginx:latest *:10080->80/tcp
[root@vm1 ~]# ss -ntl | grep 10080
LISTEN 0 128 *:10080 *:*
[root@vm1 ~]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
3ddd0e479de6 nginx:latest "/docker-entrypoint.…" 7 minutes ago Up 7 minutes 80/tcp nginx-cluster.1.6i1ncpnncxzxmsckwyahj9f7l
[root@vm1 ~]# docker port nginx-cluster.1.6i1ncpnncxzxmsckwyahj9f7l
[root@vm1 ~]# echo $?
0
[root@vm1 ~]#
访问
[root@vm1 ~]# curl 192.168.50.100:10080
Welcome to nginx!
...
在2号机上
[root@vm2 ~]# docker service ls
ID NAME MODE REPLICAS IMAGE PORTS
r4v6w094yxl3 nginx-cluster replicated 3/3 nginx:latest *:10080->80/tcp
[root@vm2 ~]# ss -ntl
State Recv-Q Send-Q Local Address:Port Peer Address:Port Process
LISTEN 0 128 0.0.0.0:22 0.0.0.0:*
LISTEN 0 128 *:10080 *:*
LISTEN 0 128 *:2377 *:*
LISTEN 0 128 *:7946 *:*
LISTEN 0 128 [::]:22 [::]:*
[root@vm2 ~]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
6b1e246bdc34 nginx:latest "/docker-entrypoint.…" 8 minutes ago Up 8 minutes 80/tcp nginx-cluster.3.yofvioldzci3k4geve7lykyrs
0d6709372322 nginx:latest "/docker-entrypoint.…" 8 minutes ago Up 8 minutes 80/tcp nginx-cluster.2.gp7szi6348r0gfakr6v1i42ga
[root@vm2 ~]#
# 另一个容器在1号机上运行
[root@vm1 ~]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
3ddd0e479de6 nginx:latest "/docker-entrypoint.…" 9 minutes ago Up 9 minutes 80/tcp nginx-cluster.1.6i1ncpnncxzxmsckwyahj9f7l
2号上也能看到overlay网络
[root@vm2 ~]# docker network ls | grep swarm-net
xywzrf7ftwen swarm-net overlay swarm
访问2号机ip，看看转发
[root@vm2 ~]# curl 192.168.50.120:10080
Welcome to nginx!