9.7. Downloading the LOCKSS Installer using Git

This section describes how to download the LOCKSS Installer from Git, for development or troubleshooting purposes. This is not the normal way of using LOCKSS Installer; the normal way to download the LOCKSS Installer is with the LOCKSS Downloader, as described in Installing LOCKSS.

Follow these instructions as the lockss user:

You may need to install Git on the host machine. Run this command:
```
git --version
```
- If you get a version message, for example git version 2.51.0, Git is already installed and no action is needed.
- If you get an error message, for example bash: git: command not found, see Installing Git for instructions.
Go into the parent directory of your intended (or pre-existing, respectively) LOCKSS Installer Directory. This directory is the one where a lockss-installer subdirectory will (or does, respectively) exist. By default, the LOCKSS Installer Directory is $HOME/lockss-installer, which is typically /home/lockss/lockss-installer, which means the parent directory needed here is $HOME, which is typically /home/lockss. Example:
```
cd /home/lockss
```
If you have previously downloaded the LOCKSS Installer the typical way, with the LOCKSS Downloader as described in Installing LOCKSS, you need to rename your pre-existing lockss-installer directory to some substitute name $OLD_LOCKSS_INSTALLER. For instance, if $OLD_LOCKSS_INSTALLER is lockss-installer-old:
```
mv lockss-installer lockss-installer-old
```
Run this Git command to clone the lockss-installer project from GitHub:
```
git clone --config pull.rebase=true https://github.com/lockss/lockss-installer
```
Adjusting to a specific Git branch, tag or commit
By default, the Git-based LOCKSS Installer is now in the develop branch, which means that it is in its most current state of development. If this is what you need or have been directed to do, you do not to do anything. But if you need or have been directed to adjust your Git tree to a specific Git branch, tag or commit, you will need to take these steps:
1. Go into the lockss-installer directory:
  cd lockss-installer
2. Perform a Git command appropriate for your situation:
  - If you need to update the Git state to that of a given branch, use the git switch command with the correct branch name, for example:
    
    git switch feature-bugfix1
  - If you need to update the Git state to that of a given tag, use the git checkout command with the correct tag name, for example:
    
    git checkout lockss-2.0.84-beta1
  - If you need to update the Git state to that of a given commit, use the git checkout command with the correct commit identifier, for example:
    
    git checkout 85a62f0188f8dc9d884169c0115a9d5666485915
    
    Commit identifiers are SHA-1 hashes or abbreviations of SHA-1 hashes.
3. Return to the parent directory:
  cd ..

If you have previously downloaded the LOCKSS Installer the typical way, with the LOCKSS Downloader as described in Installing LOCKSS, you need to copy some of the configuration files from your old LOCKSS Installer directory $OLD_LOCKSS_INSTALLER to your new LOCKSS Installer Directory lockss-installer. For instance if $OLD_LOCKSS_INSTALLER is lockss-installer-old:
```
cp lockss-installer-old/config/*.cfg lockss-installer/config/
```