新开了阿里云的机器之后机器 ssh 过去的默认提示是：
Welcome to Ubuntu 14.04.4 LTS (GNU/Linux 3.13.0-86-generic x86_64)
* Documentation: https://help.ubuntu.com/ Welcome to aliyun Elastic Compute Service!
可以加一些内容。一共两个与之相关：
issue.net : Display a banner message before the password login prompt.
motd : Display a banner message after the user has logged in.
设置 issue.net
在下面文件中添加想要添加的内容：
# vim /etc/issue.net
在 Text to ASCII Art Generator (TAAG) 上面生成了 ASCII Art。
改 config
# vim /etc/ssh/sshd_config
搜索 Banner 并取消掉它的注释
#Banner /some/path
需要 reload ssh
# service ssh reload
motd
Message of the Day 的意思，内容放在 /etc/motd ，另外还可以用 UpdateMotd 动态生成的内容，参考 UpdateMotd 。
这里先不深究，而是直接 apt-get install landscape-common 。landscape-common 会显示一些机器的信息。
Welcome to Ubuntu 16.04 LTS (GNU/Linux 4.4.0-28-generic x86_64)
* Documentation: https://help.ubuntu.com
* Management: https://landscape.canonical.com
* Support: https://ubuntu.com/advantage
System information as of Tue Jul 12 10:21:51 MDT 2016
System load: 0.09
Users logged in: 1
Usage of /: 12.3% of 225.17GB IP address for enp7s0: 192.168.X.XXX
Memory usage: 45%
IP address for wlp9s1: 192.168.X.XXX Swap usage: 0%
IP address for docker0: 172.17.0.1
Processes: 397 Graph this data and manage this system at:https://landscape.canonical.com/ 0 packages can be updated. 0 updates are security updates.
Last login: Tue Jul 12 10:03:16 2016 from 192.168.X.XXX