Want to upgrade from Piwik 1.1.2 to 2.7 (no replies)

Hi,

are they any issues I have to take care about updating from piwik 1.1.2 to 2.7?

My database takes up 1.4 gig of space. How should I ideally backup before?

Thanks for hints.

Edit: sorry, wrong forum - could anybody move my post?