Docker实践(1)—入门
tutorial
centos6.5环境。
# yum install docker-io -y
会依赖安装libcgroup，lxc，lxc-libs
启动docker
# service docker start
Starting cgconfig service: [确定]
Starting docker: [确定]
获取最新的docker image
# docker pull centos:latest
运行image
# docker run -i -t centos /bin/bash
bash-4.2# ls
bin dev etc home lib lib64 lost+found media mnt opt proc root run sbin selinux srv sys tmp usr var
bash-4.2# exit
提交更新
# docker commit -m="add net-tools" -a="dbyin" ad6327a8e166 dbyin/testrep
15a31c1fd4dd1a514b8d771e456fd9adfe206a70e4a672057363322c8b918a3a
删除镜像
# docker rmi dbyin/sshd
Untagged: dbyin/sshd:latest
Deleted: 3e6ddcc38145770486dbd2fcb5b3a6734fea447ab024c540e83d34acc8113a11
Deleted: ab8ed0aaabab96eaf1656539bb0f7990f1b114197d39308e93ab1160c222d4ff
Deleted: 4ffa765d3fafa308edba9de3e59582451d6658e4c50cf9d107bc18bfe415d2e9
Deleted: 95cc1fd701f6961585196a0b43e06404aa81f4ec65278d2249ad0716a2cf3d87
Deleted: ae21b4f05d98ea18aff9c4ed33343c933f6f11c8adb5342ab7e1ded6af8c5fd8
主要参考
[1]https://docs.docker.com/installation/centos/
通过docker部署ssh
# cat Dockerfile
FROM centos
MAINTAINER dbyin
RUN yum install -y openssh-server
RUN echo "root:root" | chpasswd
EXPOSE 22
CMD ["/usr/sbin/sshd", "-D"]
构建镜象
# docker build --rm -t dbyin/sshd .
Sending build context to Docker daemon 74.75 kB
Sending build context to Docker daemon
Step 0 : FROM centos
---> 1a7dc42f78ba
Step 1 : MAINTAINER dbyin
---> Running in f40dd8c16027
---> ae21b4f05d98
Removing intermediate container f40dd8c16027
Step 2 : RUN yum install -y openssh-server
---> Running in a298b82f5fc1
Loaded plugins: fastestmirror
Determining fastest mirrors
* base: mirrors.cug.edu.cn
* extras: mirrors.cug.edu.cn
* updates: mirrors.cug.edu.cn
Resolving Dependencies
--> Running transaction check
---> Package openssh-server.x86_64 0:6.4p1-8.el7 will be installed
--> Processing Dependency: openssh = 6.4p1-8.el7 for package: openssh-server-6.4p1-8.el7.x86_64
--> Running transaction check
---> Package openssh.x86_64 0:6.4p1-8.el7 will be installed
--> Finished Dependency Resolution
Dependencies Resolved
================================================================================
Package Arch Version Repository Size
================================================================================
Installing:
openssh-server x86_64 6.4p1-8.el7 base 367 k
Installing for dependencies:
openssh x86_64 6.4p1-8.el7 base 341 k
Transaction Summary
================================================================================
Install 1 Package (+1 Dependent package)
Total download size: 708 k
Installed size: 1.8 M
Downloading packages:
warning: /var/cache/yum/x86_64/7/base/packages/openssh-server-6.4p1-8.el7.x86_64.rpm: Header V3 RSA/SHA256 Signature, key ID f4a80eb5: NOKEY
Public key for openssh-server-6.4p1-8.el7.x86_64.rpm is not installed
--------------------------------------------------------------------------------
Total 195 kB/s | 708 kB 00:03
Retrieving key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
Importing GPG key 0xF4A80EB5:
Userid : "CentOS-7 Key (CentOS 7 Official Signing Key) <security@centos.org>"
Fingerprint: 6341 ab27 53d7 8a78 a7c2 7bb1 24c6 a8a7 f4a8 0eb5
Package : centos-release-7-0.1406.el7.centos.2.3.x86_64 (@CentOS/$releasever)
From : /etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Installing : openssh-6.4p1-8.el7.x86_64 1/2
Installing : openssh-server-6.4p1-8.el7.x86_64 2/2
Verifying : openssh-server-6.4p1-8.el7.x86_64 1/2
Verifying : openssh-6.4p1-8.el7.x86_64 2/2
Installed:
openssh-server.x86_64 0:6.4p1-8.el7
Dependency Installed:
openssh.x86_64 0:6.4p1-8.el7
Complete!
---> 95cc1fd701f6
Removing intermediate container a298b82f5fc1
Step 3 : RUN echo "root:root" | chpasswd
---> Running in 0aad665d3d2a
---> 4ffa765d3faf
Removing intermediate container 0aad665d3d2a
Step 4 : EXPOSE 22
---> Running in f3e0c11abc3f
---> ab8ed0aaabab
Removing intermediate container f3e0c11abc3f
Step 5 : CMD ["/usr/sbin/sshd", "-D"]
---> Running in 41d15fb205ff
---> 3e6ddcc38145
Removing intermediate container 41d15fb205ff
Successfully built 3e6ddcc38145
启动镜像
# docker run -d -P --name test_sshd dbyin/sshd
1348cf06d04b6b558e025e78d13b8f61d64e63301de06c8fc1da5c4d18c9b8f8
container的22被映射到host的49153端口。
停止container
# docker stop test_sshd
删除container
# docker rm test_sshd
错误1
Error: Cannot start container f82d9d3548b4d19cfb4599bb3b27f74b6d605f167456d509df722c749fdf476f: port has already been allocated
重启docker服务，参见https://github.com/dotcloud/docker/issues/6476
错误2
# ssh root@172.16.213.129 -p 49153 -v
OpenSSH_5.3p1, OpenSSL 1.0.1e-fips 11 Feb 2013
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug1: Connecting to 172.16.213.129 [172.16.213.129] port 49153.
debug1: Connection established.
debug1: permanently_set_uid: 0/0
debug1: identity file /root/.ssh/identity type -1
debug1: identity file /root/.ssh/identity-cert type -1
debug1: identity file /root/.ssh/id_rsa type -1
debug1: identity file /root/.ssh/id_rsa-cert type -1
debug1: identity file /root/.ssh/id_dsa type -1
debug1: identity file /root/.ssh/id_dsa-cert type -1
debug1: Remote protocol version 2.0, remote software version OpenSSH_6.4
debug1: match: OpenSSH_6.4 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_5.3
debug1: SSH2_MSG_KEXINIT sent
Read from socket failed: Connection reset by peer
增加以下内容重新构建镜像
RUN ssh-keygen -t rsa -f /etc/ssh/ssh_host_rsa_key
RUN ssh-keygen -t dsa -f /etc/ssh/ssh_host_dsa_key
然后出现
。。。
debug1: Exit status 254
增加以下内容重新构建镜像，参考这里
RUN sed -ri 's/UsePAM yes/#UsePAM yes/g' /etc/ssh/sshd_config
RUN sed -ri 's/#UsePAM no/UsePAM no/g' /etc/ssh/sshd_config
访问
# ssh root@172.16.213.129 -p 49153
主要参考
[1]Dockerizing an SSH Daemon Service
[2]Docker: Using Linux Containers to Support Portable Application Deployment
作者：YY哥
出处：http://www.cnblogs.com/hustcat/
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