Ubuntu basic settings: installation and use of openssh-server

Ubuntu version: 17.10
devops@ubuntu:~$ cat /etc/issue
Ubuntu 17.10 \n \l
devops@ubuntu:~$ 
devops@ubuntu:~$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 17.10
Release: 17.10
Codename: artful
devops@ubuntu:~$

devops@ubuntu:~$ sudo su
[sudo] password for devops: 
root@ubuntu:/home/devops# 
root@ubuntu:/home/devops# apt install openssh-server
Reading package lists... Done
Building dependency tree    
Reading state information... Done
openssh-server is already the newest version (1:7.5p1-10ubuntu0.1).
0 upgraded, 0 newly installed, 0 to remove and 55 not upgraded.
root@ubuntu:/home/devops# 
root@ubuntu:/home/devops# ssh -V
OpenSSH_7.5p1 Ubuntu-10ubuntu0.1, OpenSSL 1.0.2g 1 Mar 2016
root@ubuntu:/home/devops# 
root@ubuntu:/home/devops# /etc/init.d/ssh status
● ssh.service – OpenBSD Secure Shell server
  Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enabled)
  Active: active (running) since Sat 2018-03-03 07:58:44 CST; 51min ago
 Process: 3072 ExecReload=/bin/kill -HUP $MAINPID (code=exited, status=0/SUCCESS)
 Process: 3071 ExecReload=/usr/sbin/sshd -t (code=exited, status=0/SUCCESS)
 Process: 3167 ExecStartPre=/usr/sbin/sshd -t (code=exited, status=0/SUCCESS)
 Main PID: 3179 (sshd)
  Tasks: 1 (limit: 4915)
  Memory: 1.0M
   CPU: 7ms
  CGroup: /system.slice/ssh.service
      └─3179 /usr/sbin/sshd -D
Mar 03 07:58:44 ubuntu systemd[1]: Starting OpenBSD Secure Shell server...
Mar 03 07:58:44 ubuntu systemd[1]: Started OpenBSD Secure Shell server.
Mar 03 07:58:44 ubuntu sshd[3179]: Server listening on 0.0.0.0 port 22.
Mar 03 07:58:44 ubuntu sshd[3179]: Server listening on :: port 22.
root@ubuntu:/home/devops# 
root@ubuntu:/home/devops# /etc/init.d/ssh restart
[ ok ] Restarting ssh (via systemctl): ssh.service.
root@ubuntu:/home/devops#

liumiaocn:~ liumiao$ ssh [email protected]
[email protected]'s password: 
Welcome to Ubuntu 17.10 (GNU/Linux 4.13.0-21-generic x86_64)
 * Documentation: https://help.ubuntu.com
 * Management: https://landscape.canonical.com
 * Support: https://ubuntu.com/advantage
58 packages can be updated.
32 updates are security updates.
Last login: Sat Mar 3 07:43:23 2018 from 192.168.31.242
devops@ubuntu:~$