Ubuntu 11.10 source method change:
Use CTRL + ALT + T to open the terminal:
Run the following command: sudo gedit/etc/APT/sources. List // to open the software source list, copy the following source to the beginning of the file, save and exit.
Sudo apt-Get update // update the source list
Sudo apt-Get upgrade // this step is to update the software
The IPv6 source of HKUST:
# USTC
Deb http://debian.ustc.edu.cn/ubuntu/ oneiric main restricted universe multiverse
Deb http://debian.ustc.edu.cn/ubuntu/ oneiric-backports restricted universe multiverse
Deb http://debian.ustc.edu.cn/ubuntu/ oneiric-proposed main restricted universe multiverse
Deb http://debian.ustc.edu.cn/ubuntu/ oneiric- security main restricted universe multiverse
Deb http://debian.ustc.edu.cn/ubuntu/ oneiric-Updates main restricted universe multiverse
Deb-Src http://debian.ustc.edu.cn/ubuntu/ oneiric-backports main restricted universe multiverse
Deb-Src http://debian.ustc.edu.cn/ubuntu/ oneiric-proposed main restricted universe multiverse
Deb-Src http://debian.ustc.edu.cn/ubuntu/ oneiric-security main primary universe multiverse
Deb-Src http://debian.ustc.edu.cn/ubuntu/ oneiric- updates main restricted universe multiverse