Ubuntu自带更新程序默认的nginx并非新版，要安装最新的nginx，以stable版为例（1.2.10），最简便方法是：
add-apt-repository ppa:nginx/stable
apt-get update
apt-get install nginx
或者
apt-key add nginx_signing.key
deb http://nginx.org/packages/ubuntu/ codename nginx
deb-src http://nginx.org/packages/ubuntu/ codename nginx
ubuntu的codename：
12.04 precise x86_64, i386
14.04 trusty x86_64, i386, aarch64/arm64
16.04 xenial x86_64, i386, ppc64el
16.10 yakkety x86_64, i386
debian上可以在/etc/apt/sources.list.d/中新建nginx.list文件
deb http://nginx.org/packages/debian/ codename nginx
deb-src http://nginx.org/packages/debian/ codename nginx
codename是指不同的debian版本号对应不同的codename
Version Codename Supported Platforms
7.x wheezy x86_64, i386
8.x jessie x86_64, i386
之后分别运行：
curl http://nginx.org/keys/nginx_signing.key | apt-key add -
apt-get update
apt-get install nginx
还可以编译安装，比较麻烦一些，教程戳这里