Ubutun version update iteration is too fast ~ regular version of the maintenance period is relatively short, basic within one year, only like 10.04,12.04,14.04 and later 16.04 Will support the 3-5 year long.
Last year installed the latest 13.04 has stopped maintenance for several months, previously found no updates and no tube, the following want to install some software to find the source has been invalid.
After a long time to find a way, all stop maintenance version can use old source.
Writing is not easy, reproduced please indicate the source: http://blog.csdn.net/jscese/article/details/39010273
1, first backup Ubuntu 11.04 source list
sudo cp/etc/apt/sources.list/etc/apt/sources.list.backup (the current source list under Backup) 2, modify the /etc/apt/sources.list:
$sudo gedit /etc/apt/sources.list
Replace all source addresses with Http://old-releases.ubuntu.com/ubuntu, and be careful not to delete the following system versions and categories.
Deb Http://old-releases.ubuntu.com/ubuntu raring main restricted universe multiverse
Deb Http://old-releases.ubuntu.com/ubuntu raring-security main restricted universe multiverse
Deb Http://old-releases.ubuntu.com/ubuntu raring-updates main restricted universe multiverse
Deb Http://old-releases.ubuntu.com/ubuntu raring-proposed main restricted universe multiverse
Deb Http://old-releases.ubuntu.com/ubuntu raring-backports main restricted universe multiverse
DEB-SRC Http://old-releases.ubuntu.com/ubuntu raring main restricted universe multiverse
DEB-SRC http://old-releases.ubuntu.com/ubuntu raring-security main restricted universe multiverse
DEB-SRC http://old-releases.ubuntu.com/ubuntu raring-updates main restricted universe multiverse
DEB-SRC http://old-releases.ubuntu.com/ubuntu raring-proposed main restricted universe multiverse
DEB-SRC http://old-releases.ubuntu.com/ubuntu raring-backports main restricted universe multiverse
Can see the URL is all Http://old-releases.ubuntu.com/ubuntu, where each line of raring for version code, 13.04 code-named raring.
Other versions of the source can be copy above the original sources.list and then change to their corresponding version code.
sudo apt-get update
sudo pat-get upgrade
Update System ~