Docker Swarm 入门示例7: 滚动更新服务

1. 打开manager1服务器 shell

2. 部署redis 3.0.6 到swarm,并设置更新延迟为 10s

   $ docker service create \
       --replicas 3 \
       --name redis \
       --update-delay 10s \
       redis:3.0.6-alpine
   fnrfiohgr39tjae2jia5t4ox3
   
   

   --update-delay: 更新服务任务(Task)执行间隔， 单位 s,m,h --update-parallelism: 并行更新服务任务数量， 默认1 RUNNING： 更新服务任务返回RUNNING表示任务成功 FAILED: 更新服务任务返回FAILED表示任务成功 --update-failure-action: 如果更新服务任务失败后的操作，默认pause即暂停更新，结束该任务

3. 查看 redis 服务信息

   $ docker service inspect --pretty redis
   
   ID:             fnrfiohgr39tjae2jia5t4ox3
   Name:           redis
   Service Mode:   Replicated
    Replicas:      3
   Placement:
   UpdateConfig:
    Parallelism:   1
    Delay:         10s
    On failure:    pause
    Monitoring Period: 5s
    Max failure ratio: 0
    Update order:      stop-first
   RollbackConfig:
    Parallelism:   1
    On failure:    pause
    Monitoring Period: 5s
    Max failure ratio: 0
    Rollback order:    stop-first
   ContainerSpec:
    Image:         redis:3.0.6-alpine@sha256:404a3444162e8c6f7c375a27746d7b75554e1a89436bd0dc7503af25ae50cdcb
   Resources:
   Endpoint Mode:  vip
   
   

4. 更新redis 版本 更新计划

   • 停止第一个任务（容器）
   • 添加更新调度到此任务
   • 启动更新后的容器
   • 如果任务执行结果为RUNNING, 等待 delay 设置的时间后开始下一个任务
   • 如果有任意一个任务失败，停止此次更新

   $ docker service update --image redis:3.0.7 redis
   redis
   
   

5. 查看更新后的服务信息

   $ docker service inspect --pretty redis
   
   ID:             fnrfiohgr39tjae2jia5t4ox3
   Name:           redis
   Service Mode:   Replicated
    Replicas:      3
   UpdateStatus:
    State:         updating
    Started:       18 seconds ago
    Message:       update in progress
   Placement:
   UpdateConfig:
    Parallelism:   1
    Delay:         10s
    On failure:    pause
    Monitoring Period: 5s
    Max failure ratio: 0
    Update order:      stop-first
   RollbackConfig:
    Parallelism:   1
    On failure:    pause
    Monitoring Period: 5s
    Max failure ratio: 0
    Rollback order:    stop-first
   ContainerSpec:
    Image:         redis:3.0.7@sha256:730b765df9fe96af414da64a2b67f3a5f70b8fd13a31e5096fee4807ed802e20
   Resources:
   Endpoint Mode:  vip
   

6. 查看更新过程中的容器状态

   $ docker service ps redis
   ID                  NAME                IMAGE                NODE                DESIRED STATE       CURRENT STATE                 ERROR               PORTS
   9uzdoruo0n27        redis.1             redis:3.0.7          ubuntu-1604-002     Running             Preparing 23 seconds ago
   uzabimd9ilx5         \_ redis.1         redis:3.0.6-alpine   ubuntu-1604-002     Shutdown            Shutdown 21 seconds ago
   6lhvz3aanelv        redis.2             redis:3.0.6-alpine   ubuntu-1604-003     Running             Running about an hour ago
   i55mt8fzqqbp        redis.3             redis:3.0.7          ubuntu-1604-001     Running             Running 33 seconds ago
   rxu3t1iy6qcg         \_ redis.3         redis:3.0.6-alpine   ubuntu-1604-001     Shutdown            Shutdown about a minute ago