The Linode Library has proved invaluable lately. I believe they may have one of the most comprehensive solutions for properly installing MongoDB out there. The best part, to me, is that they have separate walkthroughs for Debian, Fedora, CentOS, and Ubuntu. I would highly recommend checking out these guides when you prepare for your next (or first) MongoDB install. They not only cover the actual install, but they cover setting up bash scripts, adding Mongo to your system startup, and other useful tidbits.

• Install and Setup MongoDB on Debian 5 (Lenny)
• Install and Setup MongoDB on Ubuntu 9.10 (Karmic)
• Install and Setup MongoDB on Ubuntu 10.04 (Lucid)
• Install and Setup MongoDB on CentOS 5
• Install and Setup MongoDB on Fedora 13
• Install and Setup MongoDB on Fedora 12
• Build Database Clusters with MongoDB

A word of warning; The Database Clusters guide is slightly dated with the new release of Mongo 1.6. The documentation contains information for setting up Replica Pairs and not Replica Sets. The document is, however, a good source of information for setting up quick master/slave replication with 2 nodes.

Happy installation, it’s really quite painless!