1、一般我们安装好ubuntu系统后，首先就是更换国内的ubuntu源，使得更新及安装软件速度更快
sudo cp /etc/apt/sources.list /etc/apt/sources.list_backup 备份下sources.list
适用于 15.10 的基础配置（详细）：
deb http://cn.archive.ubuntu.com/ubuntu/ willy main restricted universe multiverse deb http://cn.archive.ubuntu.com/ubuntu/ willy-security main restricted universe multiverse deb http://cn.archive.ubuntu.com/ubuntu/ willy-updates main restricted universe multiverse deb http://cn.archive.ubuntu.com/ubuntu/ willy-backports main restricted universe multiverse ##测试版源 deb http://cn.archive.ubuntu.com/ubuntu/ willy-proposed main restricted universe multiverse
# 源码 deb-src http://cn.archive.ubuntu.com/ubuntu/ willy main restricted universe multiverse deb-src http://cn.archive.ubuntu.com/ubuntu/ willy-security main restricted universe multiverse deb-src http://cn.archive.ubuntu.com/ubuntu/ willy-updates main restricted universe multiverse deb-src http://cn.archive.ubuntu.com/ubuntu/ willy-backports main restricted universe multiverse ##测试版源 deb-src http://cn.archive.ubuntu.com/ubuntu/ willy-proposed main restricted universe multiverse
如要用于其他版本，把 willy 换成版本代号就好：
执行# apt-get update
2、查看当前的ubuntu是否安装了ssh-server服务。默认只安装ssh-client服务。
3、安装SSH
apt-get install openssh-server
4、安装完成后查看服务是否启动
/etc/init.d/ssh status or ps -e | grep sshd