1、介绍

容器是Docker的另一个核心概念。

简单地说，容器是镜像的一个运行实例，所不同的是，它带有额外的可写文件层。

如果认为虚拟机是模拟运行的一整套操作系统(提供了运行态环境和其他系统外境)和跑在上面的应用。那么Docker容器就是独立运行的一个或一组应用，以及它的必而运仃环境。

2、查看容器列表

通过docker ps命令查看正在运行的容器列表，需要查询所有的容器需要加-a参数：

docker ps

docker ps -a

3、创建容器

通过docker create 命令可以创建一个容器，这仅仅是创建，并没有启动容器。

用法：

3.1.案例

案例：创建Redis的容器。

docker create -p 16379:6379 –name redis redis:3.0

查看容器列表：

启动容器：

docker start 6e #指定容器的id，只要输入前几位即可

通过客户端进行测试：

至此，第一个docker容器就创建并且已经启动可用了。

创建并且运行容器

上面通过docker create创建了容器，然后通过docker start来启动容器，其实这种做法并不常用。

更常用的是docker run命令，这个命令的意思是创建并且启动容器。

用法：

root@itcast:~# docker run –help

Usage: docker run [OPTIONS] IMAGE [COMMAND] [ARG…]

Run a command in a new container 在一个新容器中运行一个命令。

Options:

–add-host value Add a custom host-to-IP mapping (host:ip) (default [])

-a, –attach value Attach to STDIN, STDOUT or STDERR (default [])

–blkio-weight value Block IO (relative weight), between 10 and 1000

–blkio-weight-device value Block IO weight (relative device weight) (default [])

–cap-add value Add Linux capabilities (default [])

–cap-drop value Drop Linux capabilities (default [])

–cgroup-parent string Optional parent cgroup for the container

–cidfile string Write the container ID to the file

–cpu-percent int CPU percent (Windows only)

–cpu-period int Limit CPU CFS (Completely Fair Scheduler) period

–cpu-quota int Limit CPU CFS (Completely Fair Scheduler) quota

-c, –cpu-shares int CPU shares (relative weight)

–cpuset-cpus string CPUs in which to allow execution (0-3, 0,1)

–cpuset-mems string MEMs in which to allow execution (0-3, 0,1)

-d, –detach Run container in background and print container ID 让容器在后台运行

–detach-keys string Override the key sequence for detaching a container

–device value Add a host device to the container (default [])

–device-read-bps value Limit read rate (bytes per second) from a device (default [])

–device-read-iops value Limit read rate (IO per second) from a device (default [])

–device-write-bps value Limit write rate (bytes per second) to a device (default [])

–device-write-iops value Limit write rate (IO per second) to a device (default [])

–disable-content-trust Skip image verification (default true)

–dns value Set custom DNS servers (default [])

–dns-opt value Set DNS options (default [])

–dns-search value Set custom DNS search domains (default [])

–entrypoint string Overwrite the default ENTRYPOINT of the image

-e, –env value Set environment variables (default [])

–env-file value Read in a file of environment variables (default [])

–expose value Expose a port or a range of ports (default [])

–group-add value Add additional groups to join (default [])

–health-cmd string Command to run to check health

–health-interval duration Time between running the check

–health-retries int Consecutive failures needed to report unhealthy

–health-timeout duration Maximum time to allow one check to run

–help Print usage

-h, –hostname string Container host name

-i, –interactive Keep STDIN open even if not attached

–io-maxbandwidth string Maximum IO bandwidth limit for the system drive (Windows only)

–io-maxiops uint Maximum IOps limit for the system drive (Windows only)

–ip string Container IPv4 address (e.g. 172.30.100.104)

–ip6 string Container IPv6 address (e.g. 2001:db8::33)

–ipc string IPC namespace to use

–isolation string Container isolation technology

–kernel-memory string Kernel memory limit

-l, –label value Set meta data on a container (default [])

–label-file value Read in a line delimited file of labels (default [])

–link value Add link to another container (default [])

–link-local-ip value Container IPv4/IPv6 link-local addresses (default [])

–log-driver string Logging driver for the container

–log-opt value Log driver options (default [])

–mac-address string Container MAC address (e.g. 92:d0:c6:0a:29:33)

-m, –memory string Memory limit

–memory-reservation string Memory soft limit

–memory-swap string Swap limit equal to memory plus swap: ‘-1’ to enable unlimited swap

–memory-swappiness int Tune container memory swappiness (0 to 100) (default -1)

–name string Assign a name to the container

–network string Connect a container to a network (default “default”)

–network-alias value Add network-scoped alias for the container (default [])

–no-healthcheck Disable any container-specified HEALTHCHECK

–oom-kill-disable Disable OOM Killer

–oom-score-adj int Tune host’s OOM preferences (-1000 to 1000)

–pid string PID namespace to use

–pids-limit int Tune container pids limit (set -1 for unlimited)

–privileged Give extended privileges to this container

-p, –publish value Publish a container’s port(s) to the host (default [])

-P, –publish-all Publish all exposed ports to random ports

–read-only Mount the container’s root filesystem as read only

–restart string Restart policy to apply when a container exits (default “no”)

–rm Automatically remove the container when it exits

–runtime string Runtime to use for this container

–security-opt value Security Options (default [])

–shm-size string Size of /dev/shm, default value is 64MB

–sig-proxy Proxy received signals to the process (default true)

–stop-signal string Signal to stop a container, SIGTERM by default (default “SIGTERM”)

–storage-opt value Storage driver options for the container (default [])

–sysctl value Sysctl options (default map[])

–tmpfs value Mount a tmpfs directory (default [])

-t, –tty Allocate a pseudo-TTY

–ulimit value Ulimit options (default [])

-u, –user string Username or UID (format: <name|uid>[:<group|gid>])

–userns string User namespace to use

–uts string UTS namespace to use

-v, –volume value Bind mount a volume (default [])

–volume-driver string Optional volume driver for the container

–volumes-from value Mount volumes from the specified container(s) (default [])

-w, –workdir string Working directory inside the container

4.1案例

创建并且运行一个redis容器，它的端口是16380。

docker run -p 16380:6379 –name redis2 redis:3.0

发现，这个容器已经创建并且运行，但是，它并没有在后台运行，当按下 control + c时，该容器将停止。

为了让容器在后台运行，需要添加参数 -d。

docker run -p 16380:6379 -d –name redis2 redis:3.0

报错，说redis2这个名字的容器已经存在，需要我们删除906的容器或者给新容器重命名。我们重命名试试。

docker run -p 16380:6379 -d –name redis3 redis:3.0

已经创建成功。

进行测试：

测试结果显示，该容器可用。

接下来，我看下当前运行的容器：

可以看到，有3个redis的容器，并且名为redis2的容器已经退出，并没有运行。

那么问题来了，redis2这个容器我不想要了，怎么删除？

5、启动/停止容器

5.1.启动容器

root@itcast:~# docker start –help

Usage: docker start [OPTIONS] CONTAINER [CONTAINER…]

Start one or more stopped containers

Options:

-a, –attach Attach STDOUT/STDERR and forward signals

–detach-keys string Override the key sequence for detaching a container

–help Print usage

-i, –interactive Attach container’s STDIN

用法：docker start 容器名或容器id

5.2. 停止容器

停止容器有2种方式：

1、 docker stop 容器名或容器id

2、 docker kill 容器名或容器id

root@itcast:~# docker stop –help

Usage: docker stop [OPTIONS] CONTAINER [CONTAINER…]

Stop one or more running containers

Options:

–help Print usage

-t, –time int Seconds to wait for stop before killing it (default 10)

root@itcast:~# docker kill –help

Usage: docker kill [OPTIONS] CONTAINER [CONTAINER…]

Kill one or more running containers

Options:

–help Print usage

-s, –signal string Signal to send to the container (default “KILL”)

6、删除容器

通过命令docker rm 删除容器，删除正在运行的容器添加 -f 参数。

root@itcast:~# docker rm –help

Usage: docker rm [OPTIONS] CONTAINER [CONTAINER…]

Remove one or more containers

Options:

-f, –force Force the removal of a running container (uses SIGKILL)

–help Print usage

-l, –link Remove the specified link

-v, –volumes Remove the volumes associated with the container

案例：

docker rm redis2

删除名为redis2的容器。

7、进入容器

有些时候我们需要进入容器内，做一些操作，比如，修改配置文件等。

进入容器，通过命令 docker exec 完成。

root@itcast:~# docker exec –help

Usage: docker exec [OPTIONS] CONTAINER COMMAND [ARG…]

Run a command in a running container

-d, –detach Detached mode: run command in the background

–detach-keys Override the key sequence for detaching a container

–help Print usage

-i, –interactive Keep STDIN open even if not attached

–privileged Give extended privileges to the command

-t, –tty Allocate a pseudo-TTY

-u, –user Username or UID (format: <name|uid>[:<group|gid>])

案例：进入redis容器，。

docker exec -it redis /bin/bash

control + d 退出容器。

8、查看日志

通过命令docker logs -f 容器名或id

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