原文：http://www.cnblogs.com/yuxc/archive/2012/08/24/2653915.html
在使用apt-get安装包的时候，常常会遇到apt-get会建议的包，但实际上却木有安装：
root@Pure:/etc/puppet/modules/apache# apt-get install ipython
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following extra packages will be installed:
python-configobj python-simplegeneric
Suggested packages:
ipython-doc ipython-notebook ipython-qtconsole python-matplotlib python-zmq
The following NEW packages will be installed:
ipython python-configobj python-simplegeneric
0 upgraded, 3 newly installed, 0 to remove and 388 not upgraded.
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需要让apt-get默认下载推荐和建议的包，需要建立一个配置文件：/etc/apt/apt.conf：
APT::Install-Recommends "true";
APT::Install-Suggests "true";
然后在安装的时候就会默认下载了。
如果不希望apt-get下载suggested的包：
apt-get --no-install-recommends install package