Installing Mongodb on Ubuntu 10.10: A gotcha

There are already a lot of guides on how to install mongodb on Ubuntu. They all have basically the same instructions (which DO NOT WORK at a certain point, at least for me). Here is one version:

http://yoodey.com/how-install-mongodb-ubuntu-maverick-meerkat-1010-easy-steps

The tricky part is this step:

Add deb http://downloads.mongodb.org/distros/ubuntu 10.10 10gen into /etc/apt/source.list.

If you’re like me, what you do is open up your computer window, go to etc, go to apt, and then double click on sources.list. Then you go to the Other Software tab, and you click the Add button. In the dialog box that appears, you fill in deb http://downloads.mongodb.org/distros/ubuntu 10.10 10gen

If you then try to close the sources list, you’ll find that it is unable to update, and everything goes wrong. You can’t get mongodb. But the fix is easy!

It turns out that when you go through the add source process above, you end up adding two sources: a binary version, and a source version. So you’ll see, in the list, two identical sources that say “http://downloads-distro.mongodb.org/blahblah”. You only want the binary one, so if you delete the one that says something about “source”, and then try closing the list, everything will be work.

So that’s how you solve the gotcha that plagued me for an hour today.