How do I change mirrors in Ubuntu Server from regional to main?

Question

I have a Lucid Server (10.04) set up and I would like to change the mirror from US (or any other country) to the Main Ubuntu Mirror.

For example my two first entries in sources.list are:

deb http://us.archive.ubuntu.com/ubuntu/ lucid main restricted
deb-src http://us.archive.ubuntu.com/ubuntu/ lucid main restricted

In a Desktop environment I would select the main mirror like this:

But how do I do that from the terminal as I don't have a graphical environment installed!

Answer 1

Open your sources.list file using your favorite text editor, e.g.

sudo nano /etc/apt/sources.list

Locate the text http://us.archive.ubuntu.com/ubuntu and replace it with http://archive.ubuntu.com/ubuntu.

Answer 2

This command should do the trick

sudo sed -i 's/http:\/\/us./http:\/\//g' /etc/apt/sources.list

It will remove the 'us.' prefix in each of the addresses to convert them to addresses of the main server.

Of course replace 'us' by any other mirror you are using.

In depth explanation of command:

sed - stream editor for filtering and transforming text.

• The -i argument is to edit a file in place.

• Then 's/regexp/replacement/g', s specifying the search and replace command.

• The g at the end being the argument to "globally" search.

• The forward slash is the delimiter between the command and arguments except where it is escaped with a backslash.

• Conclusion: replaces all occurrences of http://us. with http:// in the file /etc/apt/sources.list.

Note: if your replacement text has forward slashes, it may be clearer to use a pipe as the sed delimiter (ref http://backreference.org/2010/02/20/using-different-delimiters-in-sed/), e.g.:

sudo sed -i 's|http://us.|http://|g' /etc/apt/sources.list

Answer 3

Or use vim

mv /etc/apt/{sources.list, sources.list.bak} # you may want make a backup
vim /etc/apt/source.list

type :(you need to hold shift) and then input

%s/http:\/\/us\./http:\/\//g

finally hit enter