What is this?

This git repository contains a set of system scripts and utilities commonly uset to maintain Debian GNU/Linux systems. Some of the scripts are used to setup firewalling, encrypted partitions, or to regularly perform maintenances through cron jobs.

Scripts are grouped by what they are used for, read the next few sections to know more.

Note also that most of the scripts are fairly well self documented. To read the documentation, either open the script in your editor, or run perldoc /path/to/scriptname. You must have the package perldoc installed on your system (apt-get install perl-doc).

Managing encrypted volumes

Let's say you have a linux server in a remote datacenter and you want to keep all of your users data encrypted, while still maintaining the ability to reboot the system without being there, a common solution is to:

1. Have an encrypted root that can boot without manual interactions. From this root, start ssh and only basic services.
2. When the system reboots, connect via ssh, mount the encrypted volumes and continue the boot process.

There are several ways to achieve this. In this repository, you can find:

• ac-dmcrypt-manage

  It allows you to manage, mount, and unmount encrypted volumes by storing keys on an encrypted partition, and using a single passphrase to access keys. Use this tool to setup encrypted partitions.

• ac-system-boot

  It allows you to mount encrypted partitions and restart services with a single command. It is handy if you keep, for example, your mysql or http data encrypted. In this case, you want to not start mysql (or apache) until the necessary partitions are mounted. By invoking ac-system-boot, your encrypted partitions will be started and the systems that depend on them will be restarted.

How to use the two scripts:

1. Create a set of encrypted volumes using ac-dmcrypt-manage create-volume. You can now mount them by using ac-dmcrypt-manage start.

2. If you have services running on your system that depend on those volumes, run ac-system-boot add servicename, where servicename is the name of the service you would use with /etc/init.d/servicename restart or service servicename restart.

3. Next time your system is rebooted, the encrypted partitions and those services will not start automatically. All you have to do is run ac-system-boot start. It will mount the encrypted partitions, and start all the services.

Cron jobs and periodic tasks

The cron directory contains several scripts useful as cron jobs. In particular:

• mysql_backup

  Backs up all of your mysql tables. Takes two arguments: a path, where to store the backup of your mysql tables, and a number, indicating how many to keep. Requires "savelog" to be available on your system.

• mysql_db_{optimize,check_changed,check_crashed}

  Those scripts have been removed from the archive. They predated the command line tool mysqlcheck. The equivalent for mysql_db_optimize is mysqlcheck -A --optimize, for mysql_check_changed mysqlcheck -A -C --auto-repair, for mysql_db_check_crashed the debian scripts should already take care of the check at mysql restart.

Other utility scripts

• ac-system-backup

  Trivial rsync wrapper to pass all the normal options you should use to backup an entire remote system.

• lsc

  Small interpreter to save typing on firewalling, traffic shaping, and many other kinds of scripts.

LICENSE

Unless otherwise specified, the code in this repository is distributed under the terms of the Gnu Public License v2.0, as available here: http://www.gnu.org/licenses/gpl-2.0.html.