docker centos7 specific steps for installing ssh

docker centos7 the specific steps to install ssh, recorded here, can also help friends reading the article.

1. Download the centos official image from docker hub

hr:centos7 hr$ docker pull centos:7 

 After downloading, view the local repository: 
hr:centos7 hr$ docker images
REPOSITORY      TAG         IMAGE ID      CREATED       VIRTUAL SIZE
  centos        7          ce20c473cd8a    7 weeks ago     172.3 MB


 Run the container 
hr:centos7 hr$ docker run -i -t centos:7 /bin/bash

2. Install passwd openssl, openssh - server

[root@b5926410fe60 /]# yum install passwd openssl openssh-server -y

 Start the sshd:
# /usr/sbin/sshd -D
 The Times has the following error: 
[root@ b5926410fe60 /]# /usr/sbin/sshd
Could not load host key: /etc/ssh/ssh_host_rsa_key
Could not load host key: /etc/ssh/ssh_host_ecdsa_key
Could not load host key: /etc/ssh/ssh_host_ed25519_key 


 Execute the following command to resolve: 
[root@b5926410fe60 /]# ssh-keygen -q -t rsa -b 2048 -f /etc/ssh/ssh_host_rsa_key -N ''  
[root@b5926410fe60 /]# ssh-keygen -q -t ecdsa -f /etc/ssh/ssh_host_ecdsa_key -N ''
[root@b5926410fe60 /]# ssh-keygen -t dsa -f /etc/ssh/ssh_host_ed25519_key -N '' 

 And then, modify  /etc/ssh/sshd_config  Configuration information: 
UsePAM yes  Instead of  UsePAM no 
UsePrivilegeSeparation sandbox  Instead of  UsePrivilegeSeparation no

[root@b5926410fe60 /]# sed -i "s/#UsePrivilegeSeparation.*/UsePrivilegeSeparation no/g" /etc/ssh/sshd_config
[root@b5926410fe60 /]# sed -i "s/UsePAM.*/UsePAM no/g" /etc/ssh/sshd_config

 After the modification, restart sshd
[root@b5926410fe60 /]# /usr/sbin/sshd -D

3. Change the root password

[root@b5926410fe60 /]# passwd root

4. View the container ip address (skip this step if the host is linux)

[root@b5926410fe60 /]# ip addr ls eth0
84: eth0@if85: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP 
  link/ether 02:42:ac:11:00:02 brd ff:ff:ff:ff:ff:ff
  inet 172.17.0.2/16 scope global eth0
    valid_lft forever preferred_lft forever
  inet6 fe80::42:acff:fe11:2/64 scope link 
    valid_lft forever preferred_lft forever

5. Save the current container as a mirror

hr:centos7 hr$ docker ps -all
CONTAINER ID IMAGE    COMMAND    CREATED       STATUS          PORTS   NAMES
b5926410fe60 centos:7  "/bin/bash" 4 minutes ago    Exited (0) 4 seconds ago      centos7ssh

hr:centos7 hr$ docker commit b5926410fe60 herong/centos7-ssh

6. Start the new container on the host based on the newly created image

-- Delete the previous container first 
hr:centos7 hr$ docker ps -all
CONTAINER ID    IMAGE   COMMAND       CREATED       STATUS           PORTS        NAMES
4122f818a741    herong/centos7-ssh:latest  "/usr/sbin/sshd"  13 seconds ago   Exited (0) 13 seconds ago            happy_mclean

hr:centos7 hr$ docker rm -f 4122f818a741


-- Run the container based on the new image 
hr:centos7 hr$ docker run -d -p 10022:22 herong/centos7-ssh:latest /usr/sbin/sshd -D

-- See if the mapped port was successful 
hr:centos7 hr$ docker ps -all
CONTAINER ID    IMAGE   COMMAND        CREATED       STATUS       PORTS          NAMES
4966d35fe0a3    herong/centos7-ssh:latest  "/usr/sbin/sshd -D"  3 seconds ago    Up 3 seconds    0.0.0.0:10022->22/tcp  compassionate_kowalevski

hr:centos7 hr$ docker port 4966d35fe0a3
22/tcp -> 0.0.0.0:10022

7. Connect from host to container

  w  If the host is wrong linux Operating system, need to pass docker-machine ip Connected to the container 
  --  To view docker-machine Ip address 
  hr:centos7 hr$ docker-machine ip default
  192.168.99.100

  -- through docker-machine ip  Connect to the container and enter the password you set to log in successfully 
  hr:centos7 hr$ ssh root@192.168.99.100 -p 10022
  The authenticity of host '[192.168.99.100]:10022 ([192.168.99.100]:10022)' can't be established.
  ECDSA key fingerprint is SHA256:d3JNckcTVv1ASJlwv+IT/bJwlzMC4U1T/PmsKYIHMhQ.
  Are you sure you want to continue connecting (yes/no)? yes
  Warning: Permanently added '[192.168.99.100]:10022' (ECDSA) to the list of known hosts.
  root@192.168.99.100's password: 
  [root@4966d35fe0a3 ~]# pwd
  /root


  w  If the host is linux Operating system, through the first 4 Step check ip Address the connection 
  hr:centos7 hr$ ssh root@172.17.0.2 -p 10022

Thank you for reading, I hope to help you, thank you for your support of this site!