新安裝的ubuntu系統，需要做下簡單的優化，使其符合常用習慣，優化過程的命令與centos大都不一致，撰文備份，以備所需：
1.獲取ubuntu系統root權限
在終端輸入sudo passwd root，按回車，然后系統會提示你輸入普通用戶的密碼(終端輸入的密碼都是不顯示的)。輸入后，按回車，然后重復輸入兩次新的root密碼即可激活root用戶。
2.安裝vim文本編輯器
輸入命令：sudo apt-get install vim-gtk
3.允許root遠程登陸
apt-get install openssh-server
修改/etc/ssh/sshd_config
注釋PermitRootLogin prohibit-password
添加PermitRootLogin yes
reload一下sshd服務即可
4.使ubuntu系統可以ssh遠程連接
需要修改/etc/ssh/ssh_config文件，去掉最后一行PermitRootLogin yes
5.關閉防火牆
ufw disable
6.更新apt-get源為阿里源
替換/etc/apt/sources.list文件中內容為：
deb-src http://archive.ubuntu.com/ubuntu xenial main restricted #Added by software-properties
deb http://mirrors.aliyun.com/ubuntu/ xenial main restricted
deb-src http://mirrors.aliyun.com/ubuntu/ xenial main restricted multiverse universe #Added by software-properties
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted multiverse universe #Added by software-properties
deb http://mirrors.aliyun.com/ubuntu/ xenial universe
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates universe
deb http://mirrors.aliyun.com/ubuntu/ xenial multiverse
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates multiverse
deb http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse #Added by software-properties
deb http://archive.canonical.com/ubuntu xenial partner
deb-src http://archive.canonical.com/ubuntu xenial partner
deb http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted multiverse universe #Added by software-properties
deb http://mirrors.aliyun.com/ubuntu/ xenial-security universe
deb http://mirrors.aliyun.com/ubuntu/ xenial-security multiverse