Upgrading Obsidian
There are a number of options available to you. Select the one that best suits your situation.
First of all, you don't need to go through the installer UI again, although you're free to do so. Since the primary purpose of the installer is to provide fully configured Obsidian artifacts and your environment would already be configured, you really just need the updated artifacts (libraries and WAR files).
Automated Installer File
This section applies if you have saved an automated installer XML file from a previous version of Obsidian.
If the release notes do not document any installer incompatibility between source and target releases, this means there are no new configuration options available and you can use your automated installer file without modification.
You can see installation configuration for more information, but essentially all you need to do is run java -jar Obsidian-Install-n-n-n.jar my-obsidian-install-config.xml. You may wish to change the target installation path before proceeding.
If the release notes do document installer incompatibility between releases, follow the relevant instructions to update your installer configuration file and then follow the same procedure.