docker基础概念

如果现在docker内运行一个ubuntu系统内的bash输出一个“hello world”那么可以这样做

[root@VM_0_9_centos ~]# docker run ubuntu:15.10 /bin/echo "hello world"
Unable to find image 'ubuntu:15.10' locally
Trying to pull repository docker.io/library/ubuntu ...
15.10: Pulling from docker.io/library/ubuntu
7dcf5a444392: Pull complete
759aa75f3cee: Pull complete
3fa871dc8a2b: Pull complete
224c42ae46e7: Pull complete
Digest: sha256:02521a2d079595241c6793b2044f02eecf294034f31d6e235ac4b2b54ffc41f3
Status: Downloaded newer image for docker.io/ubuntu:15.10
hello world

这样输出就没了。如果想在容器内交互运行的话，可以加-i -t参数

[root@VM_0_9_centos ~]# docker run -i -t  ubuntu:15.10 /bin/bash
root@13a0527cc2f3:/# hello
bash: hello: command not found
root@13a0527cc2f3:/# ll
total 72
drwxr-xr-x   1 root root 4096 Jan  7 08:09 ./
drwxr-xr-x   1 root root 4096 Jan  7 08:09 ../
-rwxr-xr-x   1 root root    0 Jan  7 08:09 .dockerenv*
drwxr-xr-x   2 root root 4096 Jul  6  2016 bin/
drwxr-xr-x   2 root root 4096 Oct 19  2015 boot/
drwxr-xr-x   5 root root  360 Jan  7 08:09 dev/
drwxr-xr-x   1 root root 4096 Jan  7 08:09 etc/
drwxr-xr-x   2 root root 4096 Oct 19  2015 home/
drwxr-xr-x   8 root root 4096 Sep 13  2015 lib/
drwxr-xr-x   2 root root 4096 Jul  6  2016 lib64/
drwxr-xr-x   2 root root 4096 Jul  6  2016 media/
drwxr-xr-x   2 root root 4096 Oct 19  2015 mnt/
drwxr-xr-x   2 root root 4096 Jul  6  2016 opt/
dr-xr-xr-x 106 root root    0 Jan  7 08:09 proc/
drwx------   2 root root 4096 Jul  6  2016 root/
drwxr-xr-x   1 root root 4096 Jan  7 08:09 run/
drwxr-xr-x   1 root root 4096 Jul 22  2016 sbin/
drwxr-xr-x   2 root root 4096 Jul  6  2016 srv/
dr-xr-xr-x  13 root root    0 Apr 11  2018 sys/
drwxrwxrwt   2 root root 4096 Jul  6  2016 tmp/
drwxr-xr-x   1 root root 4096 Jul 22  2016 usr/
drwxr-xr-x   1 root root 4096 Jul 22  2016 var/
root@13a0527cc2f3:/# cat /proc/version
Linux version 3.10.0-514.26.2.el7.x86_64 (builder@kbuilder.dev.centos.org) (gcc version 4.8.5 20150623 (Red Hat 4.8.5-11) (GCC) ) #1 SMP Tue Jul 4 15:04:05 UTC 2017
root@13a0527cc2f3:/# exit
exit
[root@VM_0_9_centos ~]#

在容器内后台执行一个进程

[root@VM_0_9_centos ~]# docker run -d ubuntu:15.10 /bin/sh -c "while true; do echo hello world; sleep 1; done"
6e851b0c97ef533cfae9c5ab7827917efa68a7a845d6c15a65be1b8e3449f16e
[root@VM_0_9_centos ~]# docker ps
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                    NAMES
6e851b0c97ef        ubuntu:15.10        "/bin/sh -c 'while..."   3 seconds ago       Up 3 seconds                                 compassionate_payne
ce8ec87e171a        docker-jialong      "sh -c 'java $JAVA..."   20 hours ago        Up 20 hours         0.0.0.0:8080->8080/tcp   laughing_ride
[root@VM_0_9_centos ~]#