Docker Mastery: Section 7 - (Swarm) Creating a 3-Node Swarm Cluster

• section7-61, 62, 63

Udemy

• Docker Mastery: with Kubernetes +Swarm from a Docker Captain

• GitHub: udemy-docker-mastery

• 講師的YouTube

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Creating 3-Node Swarm: Host Options

• A. play-with-docker.com
  • Only needs a browser, but resets after 4 hours
• B. docker-machine + VirtualBox
  • Free and runs locally, but requires a machine with 8GB memory
    • docker-machine create node1
    • docker-machine ssh node1
    • docker-machine env node1
• C. Digital Ocean + Docker install
  • Most like a production setup, but costs $5-10/node/month while learning
  • Use my referral code in section resources to get $10 free
• D. Roll your own
  • docker-machine can provision machines for Amazon, Azure, DO, Google, etc.
  • Install docker anywhere with get.docker.com

C. Digital Ocean + Docker install

• Create With Putty

  • https://www.digitalocean.com/docs/droplets/how-to/add-ssh-keys/create-with-putty/

  • Putty

• Windows: Using SSH Keys to Connect to your Droplet

  • 完美設定!

• 自行安裝 docker

  • [get.docker.com](https://get.docker.com/{:target=’_back’}

• 成功連線三台 + 完美安裝 docker

  • 

• docker swarm inint

  • 會遇到雲端常見的　multiple address

    • ` root@node1:~# docker swarm init Error response from daemon: could not choose an IP address to advertise since this system has multiple addresses on interface eth0 (128.199.251.10 and 10.15.0.5) - specify one with –advertise-addr `

  • docker searm init --advertise-addr <IP-ADDRESS>

    • root@node1:~# docker swarm init --advertise-addr 128.199.251.10
      Swarm initialized: current node (s12y6v6a9bflwg5ilgt1snqnj) is now a manager.  
      To add a worker to this swarm, run the following command:
          docker swarm join --token SWMTKN-1-3eg3s9pydsljge5als6julzr13iyr61ja55vdvi5e0i6ok0z2g-2pq15e04myfcb5tbry45kl927 128.199.251.10:2377
      To add a manager to this swarm, run 'docker swarm join-token manager' and follow the instructions.
      

• 把別人加進來 (Add a worker to this swarm)

  • docker swarm join --token <token> <IP>
    • ssh 到 node2
      • docker swarm join --token SWMTKN-1-3eg3s9pydsljge5als6julzr13iyr61ja55vdvi5e0i6ok0z2g-2pq15e04myfcb5tbry45kl927 128.199.251.10:2377
  • 把 node2 加入後
    • 到 node1 看: docker node ls

      •  　　　root@node1:~# docker node ls
         　　　ID                            HOSTNAME            STATUS              AVAILABILITY        MANAGER STATUS      ENGINE VERSION
         　　　s12y6v6a9bflwg5ilgt1snqnj *   node1               Ready               Active              Leader              19.03.5
         　　　ap6hv4cn5a169nrz9y6ekb55d     node2               Ready               Active                                  19.03.5
        

  • works cannot use any swarm cmd

    • 把 node2 變成 manager

      • docker node update --role manager node2

        • root@node1:~# docker node update --role manager node2
          node2
          root@node1:~# docker node ls
          ID                            HOSTNAME            STATUS              AVAILABILITY        MANAGER STATUS      ENGINE VERSION
          s12y6v6a9bflwg5ilgt1snqnj *   node1               Ready               Active              Leader              19.03.5
          ap6hv4cn5a169nrz9y6ekb55d     node2               Ready               Active              Reachable           19.03.5
          

• 把別人加進來 直接 default 是 manager

  • docker swarm join-token manager

    • root@node1:~# docker swarm join-token manager
      To add a manager to this swarm, run the following command:
          docker swarm join --token SWMTKN-1-3eg3s9pydsljge5als6julzr13iyr61ja55vdvi5e0i6ok0z2g-6wg4geuthyrej5yuqldd588kc 128.199.251.10:2377
      

  • ssh 到 node3 貼上

    • root@node3:~# docker swarm join --token SWMTKN-1-3eg3s9pydsljge5als6julzr13iyr61                                      
      ja55vdvi5e0i6ok0z2g-6wg4geuthyrej5yuqldd588kc 128.199.251.10:2377
      This node joined a swarm as a manager.
      

• 整體看一次

  • root@node1:~# docker node ls
    ID                            HOSTNAME            STATUS              AVAILABILITY        MANAGER STATUS      ENGINE VERSION
    s12y6v6a9bflwg5ilgt1snqnj *   node1               Ready               Active              Leader              19.03.5
    ap6hv4cn5a169nrz9y6ekb55d     node2               Ready               Active              Reachable           19.03.5
    qk9r4437q9b0hk2yzwgyyc7yf     node3               Ready               Active              Reachable           19.03.5
    

建造 三個 alpine

root@node1:~# docker service create --replicas 3 alpine ping 8.8.8.8
k9qvzxq8yopiyg3nhy0xps0dn
overall progress: 3 out of 3 tasks
1/3: running
2/3: running
3/3: running
verify: Service converged

幹！　超狂 　直接把三個 alpine 分別部屬到 node1, node2, node3

root@node1:~# docker node ls
ID                            HOSTNAME            STATUS              AVAILABILITY        MANAGER STATUS      ENGINE VERSION
s12y6v6a9bflwg5ilgt1snqnj *   node1               Ready               Active              Leader              19.03.5
ap6hv4cn5a169nrz9y6ekb55d     node2               Ready               Active              Reachable           19.03.5
qk9r4437q9b0hk2yzwgyyc7yf     node3               Ready               Active              Reachable           19.03.5
root@node1:~# docker node ps node1
ID                  NAME                IMAGE               NODE                DESIRED STATE       CURRENT STATE           ERROR               PORTS
q1m5t3k4edex        funny_franklin.1    alpine:latest       node1               Running             Running 5 minutes ago
root@node1:~# docker node ps node2
ID                  NAME                IMAGE               NODE                DESIRED STATE       CURRENT STATE           ERROR               PORTS
n2syw72rciq1        funny_franklin.2    alpine:latest       node2               Running             Running 5 minutes ago
root@node1:~# docker node ps node3
ID                  NAME                IMAGE               NODE                DESIRED STATE       CURRENT STATE           ERROR               PORTS
j6g1myeu5v4f        funny_franklin.3    alpine:latest       node3               Running             Running 5 minutes ago

• 看整個 servcie 狀況

  • docker servcie ls
  • docker servcie ps <service-name>

root@node1:~# docker service ls
ID                  NAME                MODE                REPLICAS            IMAGE               PORTS
k9qvzxq8yopi        funny_franklin      replicated          3/3                 alpine:latest
root@node1:~# docker service ps funny_franklin
ID                  NAME                IMAGE               NODE                DESIRED STATE       CURRENT STATE           ERROR               PORTS
q1m5t3k4edex        funny_franklin.1    alpine:latest       node1               Running             Running 7 minutes ago
n2syw72rciq1        funny_franklin.2    alpine:latest       node2               Running             Running 7 minutes ago
j6g1myeu5v4f        funny_franklin.3    alpine:latest       node3               Running             Running 7 minutes ago