docker run -it -d --privileged --name centos_t1 centos:latest
docker commit --change='CMD ["/usr/sbin/init"]' centos_t1 centos7_cv1
docker run -it -d --privileged --name centos_t2 centos7_cv1
docker exec -it centos_t2 /bin/bash

yum update
yum install -y vim wget epel-release net-tools iproute lrzsz nano iftop bind-utils traceroute git zsh openssh-server screen NetworkManager-tui
yum group install "Development Tools"
systemctl daemon-reload
vim /etc/ssh/sshd_config 
systemctl start sshd.service
systemctl enable sshd.service

yum install iptables-services
vim /etc/sysconfig/iptables
systemctl restart iptables.service
systemctl enable iptables.service

passwd
vim /etc/profile

  ssh-keygen -t dsa -f /etc/ssh/ssh_host_dsa_key
  ssh-keygen -t rsa -f /etc/ssh/ssh_host_rsa_key