Code snippets from my blogpost Upgrading to Lucid at the BITS Network (http://ninad.pundaliks.in/blog/2010/05/upgrading-to-lucid-at-the-bits-network/)

1.sh

~ $ :  export http_proxy="http://bitsfoss:3142/"

2.sh

~ $ :  sudo aptitude update
~ $ : sudo aptitude safe-upgrade

3.sh

~ $ :  cd /etc/apt/
$ : sudo mv sources.lst.d/ sources.lst.d.backup/
$ : sudo mkdir sources.lst.d

4.sh

$ : sudo perl -p -i.ORIG -e 's/karmic/lucid/g' /etc/apt/sources.list

5.sh

$ : sudo aptitude update

6.sh

$ : sudo aptitude install dpkg apt aptitude
$ : sudo aptitude safe-ugrade
$ : sudo aptitude full-upgrade