johannessen / setup.sh

Script framework to help setup a Debian Linux box

setup.sh

Script framework to help setup a Debian Linux box.

Upon execution, setup.sh will run all setup scripts inside the setup.d directory.

The setup.d scripts have certain tools available to them that may make configuration easier (setup.tools). One such tool is setup_copy, which copies a config file specified by path (e. g. /etc/postfix/virtual-mysql.cf) from the setup directory to the corresponding position in the file system.

setup.sh supports two separate directory trees as source for configuration files and scripts. This repository represents the "global" tree, which contains settings that are similar or identical for many hosts. A "local" tree should be added to configure a specific host.

setup.sh will automatically detect whether a config file or script is available only in the global tree, only in the local tree, or available in both. In the latter case, preference will be given to the local tree.

setup.sh runs all setup.d scripts in the same shell execution environment using the . command. This means that it's possible to set an environment variable in one script and use it in another script. However, if execution of setup.sh is aborted due to an error condition, the environment will be lost and such variables may have to be set manually using export.

Prerequisites

This version of setup.sh is designed for Debian 11 "bullseye".

When executed, setup.sh expects the following:

• $HOSTNAME_VPS contains the host's fully-qualified domain name
• The FQDN resolves to A and AAAA records
• $SETUPPATH contains the file system path to the "local" tree
• The "local" tree contains the files:
  • credentials.private (with passwords and user accounts)
  • backup.tar (backup of databases and server configuration)
  • srv.tar (backup of /srv data)

The environment variables are best supplied by a shell script in the "local" tree (see setup.example/setup.sh).

Using setup.sh for custom hosts

First of all, you need to understand that this repository's master branch may change at any time in a way that is not compatible with your situation. As a user of setup.sh, you are encouraged to clone or fork this repository, create a new branch in your clone or fork and only work with the "local" tree inside a new custom directory in that branch. This insulates your project from any upstream changes. For a demonstration of how this custom directory may look, see setup.example.

Another safe option might be to use this repository (or a fork) as a git submodule to your own project's repository. But this might be a bit harder to use.

Rationale

setup.sh is not only useful for setting up a host for the first time. It can also be used as part of an emergency response plan: In case normal operation of the host is seriously disrupted, you can simply start over with a clean slate. Assuming a current backup is available, setup.sh will quickly bring the host into a defined safe state.

However, note that upstream changes to the software used on the host may cause trouble. Major updates to the OS distribution are a particular problem. Frequent trials of setup.sh in a testing environment should help to identify and fix any issues early.

Copying

First version of setup.sh written in 2014 by Arne Johannessen.

No rights reserved.
See LICENSE for details.