参考http://wiki.ubuntu.org.cn/Qref/Source
1 首先备份源列表:
sudo cp /etc/apt/sources.list /etc/apt/sources.list_backup
sudo apt-get install gedit (gedit用习惯了)
sudo gedit /etc/apt/sources.list
我选择的是中国科学技术大学更新服务器
先ping一下:ping debian.ustc.edu.cn显示(按ctrl+c结束)
$ ping debian.ustc.edu.cn
PING mirrors.ustc.edu.cn (202.141.160.110) 56(84) bytes of data.
64 bytes from 202.141.160.110: icmp_req=1 ttl=56 time=20.0 ms
64 bytes from 202.141.160.110: icmp_req=2 ttl=56 time=21.8 ms
64 bytes from 202.141.160.110: icmp_req=3 ttl=56 time=22.8 ms
再ping mirrors.tuna.tsinghua.edu.cn哈哈差距好大
$ ping mirrors.tuna.tsinghua.edu.cn
PING mirrors.tuna.tsinghua.edu.cn (202.112.3.6) 56(84) bytes of data.
64 bytes from 202.112.3.6: icmp_req=1 ttl=54 time=59.7 ms
64 bytes from 202.112.3.6: icmp_req=2 ttl=54 time=63.7 ms
再ping一下官方的,这

$ ping archive.ubuntu.com
PING archive.ubuntu.com (91.189.92.177) 56(84) bytes of data.
64 bytes from zaurac.canonical.com (91.189.92.177): icmp_req=1 ttl=45 time=379 ms
64 bytes from zaurac.canonical.com (91.189.92.177): icmp_req=2 ttl=45 time=398 ms
64 bytes from zaurac.canonical.com (91.189.92.177): icmp_req=3 ttl=45 time=409 ms
再附上我发现的一个终端小技巧:按上下键可以切换到那次的输入来,可以省好多事啊