I use Slicehost and typically provision Debian Lenny. But, after trying to install Beanstalkd, I found out that Lenny doesn’t support the required package, libevent-dev (1.4+). Time to upgrade my slice to Squeeze.
Here’s how to do it:
Edit sources.list
sudo nano /etc/apt/sources.list
Change any word Lenny to Squeeze, (or from stable to testing) and save it. Backup your original file, just to be safe
Updating and upgrading
sudo aptitude update
sudo aptitude install apt dpkg aptitude
sudo aptitude full-upgrade
Thats it. You will be prompted with a few screens to authorize the upgrading or removal of certain packages and/or dependencies. Take note of which packages will be altered before you proceed.
After this, you should be on running Debian Squeeze. Note: It is better to use Squeeze instead of testing.