在 1Panel 上利用 Docker Swarm 实现负载均衡

Docker Swarm的概念我们就不再赘述了，这里有详细的解释。其机制类似Kubernetes（当下流行的容器编排系统），但是Swarm会更加简单易用，更适合小型项目的部署。

本文我将介绍一下如何在1Panel上利用Docker Swarm实现服务负载均衡。

前提

服务是无状态的
主服务器已经安装1Panel
了解过Docker Compose
以下步骤均不支持Podman

为了简单起见，本文不涉及多节点的搭建过程。

启用Swarm模式

如果我们想要使用Swarm模式，则需要在当前服务器上执行以下命令启用：

❯ docker swarm init
Swarm initialized: current node (ygyleqoqkt185xl2l4zczvzdm) is now a manager.

To add a worker to this swarm, run the following command:

    docker swarm join --token SWMTKN-1-5r3y44czszyyy25650hfnwtuplhar92kz9wx1ihwbh-4k8rdxxxvv2cismvw7 192.168.233.191:2377

To add a manager to this swarm, run 'docker swarm join-token manager' and follow the instructions.

这意味着当前节点已经成为了Swarm模式中的管理节点，我们可以执行以下命令获取当前节点信息：

❯ docker node ls
ID                            HOSTNAME   STATUS    AVAILABILITY   MANAGER STATUS   ENGINE VERSION
ygyleqoqkt185xl2l4zczvzdm *   fedora     Ready     Active         Leader           28.3.2

当STATUS字段为READY 则表示健康。

容器编排

我们可以利用已有的Compose规范（Compose V1）来定义容器编排，不过需要注意的是，截至目前，暂不支持最新的Compose规范（Compose V2）。

定义Compose文件

这里我们简单地定义三个Nginx服务的Compose文件，请参考下面的示例：

services:
  web:
    image: nginx:latest
    ports:
      - "8088:80"
    deploy:
      mode: replicated
      replicas: 3
      update_config:
        parallelism: 1
        delay: 5s
        order: start-first

networks:
  web-network:
    driver: overlay
    attachable: true

自定义overlay驱动的网络，主要是用于隔离各个部署（例如测试，生产环境）。

执行部署

执行以下命令可直接部署三个Nginx服务：

❯ docker stack deploy --detach=false -c nginx-compose.yaml web
Creating network web_default
Creating service web_web
overall progress: 3 out of 3 tasks 
1/3: running   [==================================================>] 
2/3: running   [==================================================>] 
3/3: running   [==================================================>] 
verify: Service 865esjcm2u9yh910koxgwj7u0 converged

执行以下命令可查看服务的细节：

❯ docker stack ls
NAME      SERVICES
web       1

❯ docker stack services web
ID             NAME      MODE         REPLICAS   IMAGE          PORTS
865esjcm2u9y   web_web   replicated   3/3        nginx:latest   *:8088->80/tcp

执行以下命令可查看当前服务运行的日志：

❯ docker service logs web_web
web_web.1.2r74tcsruvr5@fedora    | /docker-entrypoint.sh: /docker-entrypoint.d/ is not empty, will attempt to perform configuration
web_web.1.2r74tcsruvr5@fedora    | /docker-entrypoint.sh: Looking for shell scripts in /docker-entrypoint.d/
web_web.1.2r74tcsruvr5@fedora    | /docker-entrypoint.sh: Launching /docker-entrypoint.d/10-listen-on-ipv6-by-default.sh
web_web.1.2r74tcsruvr5@fedora    | 10-listen-on-ipv6-by-default.sh: info: Getting the checksum of /etc/nginx/conf.d/default.conf
web_web.1.2r74tcsruvr5@fedora    | 10-listen-on-ipv6-by-default.sh: info: Enabled listen on IPv6 in /etc/nginx/conf.d/default.conf
web_web.1.2r74tcsruvr5@fedora    | /docker-entrypoint.sh: Sourcing /docker-entrypoint.d/15-local-resolvers.envsh
web_web.1.2r74tcsruvr5@fedora    | /docker-entrypoint.sh: Launching /docker-entrypoint.d/20-envsubst-on-templates.sh
web_web.1.2r74tcsruvr5@fedora    | /docker-entrypoint.sh: Launching /docker-entrypoint.d/30-tune-worker-processes.sh
web_web.1.2r74tcsruvr5@fedora    | /docker-entrypoint.sh: Configuration complete; ready for start up
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: using the "epoll" event method
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: nginx/1.29.0
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: built by gcc 12.2.0 (Debian 12.2.0-14+deb12u1) 
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: OS: Linux 6.15.5-200.fc42.x86_64
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: getrlimit(RLIMIT_NOFILE): 1073741816:1073741816
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker processes
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 29
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 30
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 31
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 32
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 33
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 34
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 35
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 36
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 37
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 38
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 39
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 40
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 41
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 42
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 43
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 44
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 45
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 46
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 47
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 48
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 49
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 50
web_web.2.orv9gsn8fxa3@fedora    | /docker-entrypoint.sh: /docker-entrypoint.d/ is not empty, will attempt to perform configuration
web_web.2.orv9gsn8fxa3@fedora    | /docker-entrypoint.sh: Looking for shell scripts in /docker-entrypoint.d/
web_web.2.orv9gsn8fxa3@fedora    | /docker-entrypoint.sh: Launching /docker-entrypoint.d/10-listen-on-ipv6-by-default.sh
web_web.2.orv9gsn8fxa3@fedora    | 10-listen-on-ipv6-by-default.sh: info: Getting the checksum of /etc/nginx/conf.d/default.conf
web_web.2.orv9gsn8fxa3@fedora    | 10-listen-on-ipv6-by-default.sh: info: Enabled listen on IPv6 in /etc/nginx/conf.d/default.conf
web_web.2.orv9gsn8fxa3@fedora    | /docker-entrypoint.sh: Sourcing /docker-entrypoint.d/15-local-resolvers.envsh
web_web.2.orv9gsn8fxa3@fedora    | /docker-entrypoint.sh: Launching /docker-entrypoint.d/20-envsubst-on-templates.sh
web_web.2.orv9gsn8fxa3@fedora    | /docker-entrypoint.sh: Launching /docker-entrypoint.d/30-tune-worker-processes.sh
web_web.2.orv9gsn8fxa3@fedora    | /docker-entrypoint.sh: Configuration complete; ready for start up
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: using the "epoll" event method
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: nginx/1.29.0
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: built by gcc 12.2.0 (Debian 12.2.0-14+deb12u1) 
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: OS: Linux 6.15.5-200.fc42.x86_64
web_web.3.k3pacajqobit@fedora    | /docker-entrypoint.sh: /docker-entrypoint.d/ is not empty, will attempt to perform configuration
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: getrlimit(RLIMIT_NOFILE): 1073741816:1073741816
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker processes
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 29
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 30
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 31
web_web.3.k3pacajqobit@fedora    | /docker-entrypoint.sh: Looking for shell scripts in /docker-entrypoint.d/
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 32
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 33
web_web.3.k3pacajqobit@fedora    | /docker-entrypoint.sh: Launching /docker-entrypoint.d/10-listen-on-ipv6-by-default.sh
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 34
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 35
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 36
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 37
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 38
web_web.3.k3pacajqobit@fedora    | 10-listen-on-ipv6-by-default.sh: info: Getting the checksum of /etc/nginx/conf.d/default.conf
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 39
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 40
web_web.3.k3pacajqobit@fedora    | 10-listen-on-ipv6-by-default.sh: info: Enabled listen on IPv6 in /etc/nginx/conf.d/default.conf
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 41
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 42
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 43
web_web.3.k3pacajqobit@fedora    | /docker-entrypoint.sh: Sourcing /docker-entrypoint.d/15-local-resolvers.envsh
web_web.3.k3pacajqobit@fedora    | /docker-entrypoint.sh: Launching /docker-entrypoint.d/20-envsubst-on-templates.sh
web_web.3.k3pacajqobit@fedora    | /docker-entrypoint.sh: Launching /docker-entrypoint.d/30-tune-worker-processes.sh
web_web.3.k3pacajqobit@fedora    | /docker-entrypoint.sh: Configuration complete; ready for start up
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: using the "epoll" event method
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 44
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: nginx/1.29.0
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: built by gcc 12.2.0 (Debian 12.2.0-14+deb12u1) 
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 45
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: OS: Linux 6.15.5-200.fc42.x86_64
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: getrlimit(RLIMIT_NOFILE): 1073741816:1073741816
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 46
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker processes
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 29
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 47
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 30
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 31
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 48
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 32
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 33
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 49
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 34
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 35
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 36
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 50
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 37
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 38
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 39
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 40
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 41
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 42
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 43
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 44
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 45
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 46
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 47
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 48
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 49
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 50

执行以下命令可以查看实时日志：

❯ docker service logs web_web -f --tail 2
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 49
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 49
web_web.3.k3pacajqobit@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 50
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 49
web_web.2.orv9gsn8fxa3@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 50
web_web.1.2r74tcsruvr5@fedora    | 2025/07/20 16:32:53 [notice] 1#1: start worker process 50

我们再次打开新的终端，执行三次 curl -i 127.0.0.1:8088 命令查看日志输出，具体日志示例如下所示：

web_web.3.k3pacajqobit@fedora    | 10.0.0.2 - - [20/Jul/2025:16:41:25 +0000] "GET / HTTP/1.1" 200 615 "-" "curl/8.11.1" "-"
web_web.1.2r74tcsruvr5@fedora    | 10.0.0.2 - - [20/Jul/2025:16:41:26 +0000] "GET / HTTP/1.1" 200 615 "-" "curl/8.11.1" "-"
web_web.2.orv9gsn8fxa3@fedora    | 10.0.0.2 - - [20/Jul/2025:16:43:51 +0000] "GET / HTTP/1.1" 200 615 "-" "curl/8.11.1" "-"

我们发现有三个服务（web_web.1、web_web.2和web_web.3）轮流响应我们的请求。

至此，我们的服务已经成功部署好了。接下来，我们需要去1Panel侧去添加网站即可实现对外访问。

添加网站

请参考官方文档-创建网站部分。需要注意的是，端口需选择Compose文件中定义的8088端口。

伸缩服务

对外访问成功后，我们可以根据实际访问情况，添加或减少Swarm节点，伸缩服务实例。例如，我们执行下面的命令可以新增两个服务实例：

❯ docker service scale web_web=5
web_web 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 web_web converged