前言
有时需要在本地模拟多节点集群环境，通常我们会创建虚拟机作为独立的节点，但是常用的工具如VMware或Virtualbox都是基于GUI操作的：下载OS镜像、配置虚拟机、再进入多个虚拟机内安装软件，一系列操作下来比较繁琐耗时。Ubuntu推出了一个叫multipass的工具，可以基于命令行创建、配置、管理虚拟机，这使得快速、自动化地创建虚拟机成为可能。
本文探索使用multipass工具在本地快速搭建docker swarm集群环境。
核心步骤
安装multipass
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mac环境安装multipass
brew install multipass其它安装方式及multipass的使用手册请查阅官网。
创建虚拟机
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创建manager节点，规格为1cpu，500M内存，5G磁盘
multipass launch --name manager --cpus 1 --memory 512M --disk 5G命令执行成功后查看vm信息：
➜ ~ multipass info manager Name: manager State: Running IPv4: 192.168.64.13 Release: Ubuntu 22.04.3 LTS Image hash: 2461b36d86ac (Ubuntu 22.04 LTS) CPU(s): 1 Load: 0.28 0.17 0.07 Disk usage: 1.4GiB out of 4.8GiB Memory usage: 120.5MiB out of 448.3MiB Mounts: --同时mac上多了一个虚拟机进程
Multipass uses Hyper-V on Windows, QEMU and HyperKit on macOS and LXD on Linux for minimal overhead and the fastest possible start time
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创建worker节点，规格为2cpu，1G内存，10G磁盘
multipass launch --name worker --cpus 2 --memory 1G --disk 10G
为虚拟机安装docker
# 为manager节点安装docker
multipass exec manager -- sh -c 'wget -qO- https://get.docker.com | sh && sudo usermod -aG docker $USER'
# 为worker节点安装docker
multipass exec worker -- sh -c 'wget -qO- https://get.docker.com | sh && sudo usermod -aG docker $USER'
上述命令包含两个操作：
multipass exec命令可以直接在manager和worker节点虚拟机内执行用户指定命令。配置docker swarm集群
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登录manager节点，初始化docker swarm集群
# 登录manager节点 ➜ ~ multipass shell manager # 初始化docker swarm集群 ubuntu@manager:~$ docker swarm init Swarm initialized: current node (qrj2ed06u9u8hv1q42naant7u) is now a manager. To add a worker to this swarm, run the following command: docker swarm join --token SWMTKN-1-0rbktjge30ppw1o62wt9ruju7ff7neuq5y109f6i3vxxgq8myt-4fdu3c2bku48ray80pxbhiv0m 192.168.64.13:2377 To add a manager to this swarm, run 'docker swarm join-token manager' and follow the instructions. -
登录worker节点，将worker节点加入swarm集群
# 登录worker节点 ➜ ~ multipass shell worker # 将worker节点加入docker swarm集群 ubuntu@worker:~$ docker swarm join --token SWMTKN-1-0rbktjge30ppw1o62wt9ruju7ff7neuq5y109f6i3vxxgq8myt-4fdu3c2bku48ray80pxbhiv0m 192.168.64.13:2377 This node joined a swarm as a worker. -
在manager节点检查集群状态
ubuntu@manager:~$ docker node ls ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS ENGINE VERSION qrj2ed06u9u8hv1q42naant7u * manager Ready Active Leader 24.0.6 7di8oseqxypswdayrrzth9ivq worker Ready Active 24.0.6
脚本一键部署
上面我们部署了1manager + 1worker规格的最简单集群，为了模拟更真实的集群环境我们通常需要部署更多的节点，为了减少重复手工操作，使用shell脚本将上述步骤自动化。
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创建一个名为
docker-swarm-init.sh的脚本#!/bin/bashlog() {
# 使用蓝色打印关键日志
pattern=" 33[34m>> $1 33[0mn"
shift
args="$@"
printf "$pattern" $args
}# 默认配置
manager_nums=1
manager_cpus=1
manager_memory=512M
manager_disk=5Gworker_nums=1
worker_cpus=2
worker_memory=2G
worker_disk=10G# 解析参数
OPTIONS=m:w:
LONGOPTIONS=manager-nums:,worker-nums:,manager-cpus:,manager-memory:,manager-disk:,worker-cpus:,worker-memory:,worker-disk:
args=$(getopt -o "$OPTIONS" -l "$LONGOPTIONS" --name "$0" -- "$@")
## 检查解析结果是否出错
if [ $? -ne 0 ]; then
exit 1
fi
## 重新设置命令行参数
eval set -- "$args"while true; do
case "$1" in
-m | --manager-nums)
manager_nums=$2
shift
;;
--manager-cpus)
manager_cpus=$2
shift
;;
--manager-memory)
manager_memory=$2
shift
;;
--manager-disk)
manager_disk=$2
shift
;;
-w | --worker-nums)
worker_nums=$2
shift
;;
--worker-cpus)
worker_cpus=$2
shift
;;
--worker-memory)
worker_memory=$2
shift
;;
--worker-disk)
worker_disk=$2
shift
;;
--)
shift
break
;;
*)
echo "Invalid option: $1"
exit 1
;;
esac
shift
donelog "start building clusters, expected %s managers[cpus: %s, memory: %s, disk: %s], and %s workers[cpus: %s, memory: %s, disk: %s]" $manager_nums $manager_cpus $manager_memory $manager_disk $worker_nums $worker_cpus $worker_memory $worker_disk
# 创建vm实例
create_vm() {
type=$1
instance_name=$2
case "$type" in
manager)
multipass launch --name $instance_name --cpus $manager_cpus --memory $manager_memory --disk $manager_disk
;;
worker)
multipass launch --name $instance_name --cpus $worker_cpus --memory $worker_memory --disk $worker_disk
;;
*)
log "Invalid vm type: $type"
exit 1
;;
esac
log "vm $instance_name created"
}
manager_vms=()
worker_vms=()
## 创建manager vms
for ((i = 1; i
