Docker 1.12 新特性
docker 1.12 版本新特性
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docker swarm：集群管理，子命令有init, join, leave, update
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docker service：服务创建，子命令有create, inspect, update, remove
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docker node：节点管理，子命令有accept, promote, demote, inspect, update, tasks, ls, rm
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docker stack/deploy：试验特性，用于多应用部署， 类似与 docker-compose 中的特性。
如何升级？
$ curl -fsSL https://get.docker.com/ | sh
$ systemctl restart docker
集群管理
docker swarm
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init Initialize a Swarm
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join Join a Swarm as a node and/or manager
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leave Leave a Swarm
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update Update the Swarm
docker swarm init
初始化一个 swarm 集群：
$ docker swarm init
Swarm initialized: current node (0vwpni05mew2j84i6gjet44iu) is now a manager.
如果你的机器有多块网卡，则需要指定 ip 地址：
$ docker swarm init --advertise-addr 192.168.96.187
命令执行过后会返回其他节点加入时需要的 token，这个 token 也可以使用 docker swarm join-token 命令查看。
参数：
--advertise-addr string Advertised address (format: <ip|interface>[:port])
--cert-expiry duration Validity period for node certificates (default 2160h0m0s)
--dispatcher-heartbeat duration Dispatcher heartbeat period (default 5s)
--external-ca value Specifications of one or more certificate signing endpoints
--force-new-cluster Force create a new cluster from current state.
--help Print usage
--listen-addr value Listen address (format: <ip|interface>[:port]) (default 0.0.0.0:2377)
--task-history-limit int Task history retention limit (default 5)
docker swarm join
添加节点：
使用 init 时生成的 token 进行节点的添加， 添加 worker 和 manager 节点的 token 是不同的。
具体可以在初始节点上通过 docker swarm join-token (worker|manager) 命令查询。
具体命令形如：
docker swarm join \
--token SWMTKN-1-1pk90rlt0iaoqfr7kvq8qyi38n8it7tthzfv8e19l545e6uzql-1l1mhad32fcchvuhz4kjap2zd \
192.168.96.187:2377
添加过以后可以通过 docker node ls 查看当前集群节点状态。
docker swarm leave
删除节点：
在某个节点上使用 docker swarm leave 命令，可使得当前节点离开 swarm 集群。
离开后，通过 ‘ docker node ls` 命令查看节点状态时，该节点的状态变为 down。
docker swarm update
更新 swarm 集群参数，具体参数和 init 命令的参数一致。
参数：
--cert-expiry duration Validity period for node certificates (default 2160h0m0s)
--dispatcher-heartbeat duration Dispatcher heartbeat period (default 5s)
--external-ca value Specifications of one or more certificate signing endpoints
--help Print usage
--task-history-limit int Task history retention limit (default 5)
服务管理
docker service
- create Create a new service
- inspect Display detailed information on one or more services
- ps List the tasks of a service
- ls List services
- rm Remove a service
- scale Scale one or multiple services
- update Update a service
docker service create
创建一个服务：
Options:
--constraint value Placement constraints (default [])
--container-label value Container labels (default [])
--endpoint-mode string Endpoint mode (vip or dnsrr)
-e, --env value Set environment variables (default [])
--help Print usage
-l, --label value Service labels (default [])
--limit-cpu value Limit CPUs (default 0.000)
--limit-memory value Limit Memory (default 0 B)
--log-driver string Logging driver for service
--log-opt value Logging driver options (default [])
--mode string Service mode (replicated or global) (default "replicated")
--mount value Attach a mount to the service
--name string Service name
--network value Network attachments (default [])
-p, --publish value Publish a port as a node port (default [])
--replicas value Number of tasks (default none)
--reserve-cpu value Reserve CPUs (default 0.000)
--reserve-memory value Reserve Memory (default 0 B)
--restart-condition string Restart when condition is met (none, on-failure, or any)
--restart-delay value Delay between restart attempts (default none)
--restart-max-attempts value Maximum number of restarts before giving up (default none)
--restart-window value Window used to evaluate the restart policy (default none)
--stop-grace-period value Time to wait before force killing a container (default none)
--update-delay duration Delay between updates
--update-failure-action string Action on update failure (pause|continue) (default "pause")
--update-parallelism uint Maximum number of tasks updated simultaneously (0 to update all at once) (default 1)
-u, --user string Username or UID
--with-registry-auth Send registry authentication details to swarm agents
-w, --workdir string Working directory inside the container
service 和 task 的区别
在使用 docker service create 命令的时候如果添加了 --replicas 参数，也就是副本数大于1时，每个实例就是一个 task 。
$docker service create --name nginx --replicas 2 -p 80:80/tcp nginx
$docker service ls
ID NAME REPLICAS IMAGE COMMAND
1b9a58mlz330 nginx 1/2 nginx
$docker service tasks nginx
ID NAME SERVICE IMAGE LAST STATE DESIRED STATE NODE
56er48j3hin9ysdi3sb1chbn1 nginx.1 nginx nginx Preparing 2 minutes Running swarm-node-1
e7vtvpkbstznoi8ogihaao1f5 nginx.2 nginx nginx Running 2 minutes Running swarm-manager
创建一个带 rolling update 策略的服务
$ docker service create \
--replicas 10 \
--name redis \
--update-delay 10s \
--update-parallelism 2 \
redis:3.0.6
当服务更新时，则按照每10秒钟更新两个实例的策略进行更新。
设置环境变量
$ docker service create --name redis_2 --replicas 5 --env MYVAR=foo redis:3.0.6
为服务设置标签
$ docker service create \
--name redis_2 \
--label com.example.foo="bar"
--label bar=baz \
redis:3.0.6
设置模式
$ docker service create --name redis_2 --mode global redis:3.0.6
设定调度规则
| node | attribute matches | example |
|---|---|---|
| node.id | node ID | node.id == 2ivku8v2gvtg4 |
| node.hostname | node hostname | node.hostname != node-2 |
| node.role | node role: manager | node.role == manager |
| node.labels | user defined node labels | node.labels.security == high |
| engine.labels | Docker Engine’s labels | engine.labels.operatingsystem == ubuntu 14.04 |
例如：
$ docker service create \
--name redis_2 \
--label com.example.foo="bar"
--label bar=baz \
redis:3.0.6
具备 reschedule 的功能
task 挂掉以后可自动调配重新启动。
docker service scale
通过命令 docker service scale [servicename]=n 的方式来扩展服务；
也可通过该命令缩容，被缩减的 task （容器）实际是被 stop 了，而非 rm。
docker service rm
通过命令 docker service rm [servicename] 可删除一个 service 下的全部容器。
docker service update
更新 service 参数。
参数：
--args string Service command args
--constraint-add value Add or update placement constraints (default [])
--constraint-rm value Remove a constraint (default [])
--container-label-add value Add or update container labels (default [])
--container-label-rm value Remove a container label by its key (default [])
--endpoint-mode string Endpoint mode (vip or dnsrr)
--env-add value Add or update environment variables (default [])
--env-rm value Remove an environment variable (default [])
--help Print usage
--image string Service image tag
--label-add value Add or update service labels (default [])
--label-rm value Remove a label by its key (default [])
--limit-cpu value Limit CPUs (default 0.000)
--limit-memory value Limit Memory (default 0 B)
--log-driver string Logging driver for service
--log-opt value Logging driver options (default [])
--mount-add value Add or update a mount on a service
--mount-rm value Remove a mount by its target path (default [])
--name string Service name
--network-add value Add or update network attachments (default [])
--network-rm value Remove a network by name (default [])
--publish-add value Add or update a published port (default [])
--publish-rm value Remove a published port by its target port (default [])
--replicas value Number of tasks (default none)
--reserve-cpu value Reserve CPUs (default 0.000)
--reserve-memory value Reserve Memory (default 0 B)
--restart-condition string Restart when condition is met (none, on-failure, or any)
--restart-delay value Delay between restart attempts (default none)
--restart-max-attempts value Maximum number of restarts before giving up (default none)
--restart-window value Window used to evaluate the restart policy (default none)
--stop-grace-period value Time to wait before force killing a container (default none)
--update-delay duration Delay between updates
--update-failure-action string Action on update failure (pause|continue) (default "pause")
--update-parallelism uint Maximum number of tasks updated simultaneously (0 to update all at once) (default 1)
-u, --user string Username or UID
--with-registry-auth Send registry authentication details to swarm agents
-w, --workdir string Working directory inside the container
节点管理
docker node
- demote Demote a node from manager in the swarm
- inspect Display detailed information on one or more nodes
- ls List nodes in the swarm
- promote Promote a node to a manager in the swarm
- rm Remove a node from the swarm
- ps List tasks running on a node
- update Update a node