sync2usb

Wrapper script for rsync to export files to one or more USB backup drive(s).

This is not a backup script itself, but is designed to copy existing backup files off the local system and onto a removable USB drive. Therefore, it makes a few assumptions:

• You have already written your backup to disk somewhere.
• The backup files are collected in a directory.
• You want to write the files to a similarly named directory on the USB drive.
• In the case of multiple USB drives, they all have similar mount point names.
• If two or more drives are hooked up, it's okay to randomly pick one.

The script offers optional support for LVM snapshots. If your backup files are located on a Logical Volume (LV), then sync2usb can create a snapshot of the LV before starting the rsync. This should result in your backup files being internally consistent on the USB drive.

Auto-mounting of USB drives

See AUTOFS.md and LUKS.md.

Settings

The central global settings file is, by default, at /etc/sync2usb.conf. Any settings in this file will override the defaults.

Users can have their own settings files, which override any default or global settings. This file is sync2usb.conf in the user's home directory.

Individual backup jobs can also override default / global / user settings.

Configuration Variables

Global / User Variables:

job_dir - location of job files (default "sync2usb.d" in user's home directory)

lvm_snapshotadd - Amount (in GiB) to add to the LV when doing the snapshot

lvm_thinflag - (possibly not needed), 'true' if LV is a "thin" LV

lvm_vgname - Volume Group name which contains the LV (optional)

minimum_free_space - Measured in GiB (gigabytes), error if target has less, warn at 2x or less

minimum_free_inodes - Error if target file system has less, warn at 2x or less

usb_base - directory where USB backup drives are mounted

usb_prefix - space delimited list of letters/numbers used as prefixes

usb_filename - the unchanging portion of the mount directory

usb_suffix - space delimited list of letters/numbers used as suffixes

verbosity - 0=none, 1=some info, 2=debug level

Job Specific Variables:

These settings really only make sense in a *.job file.

backup_base - Location of the directory to be backed up

backup_dir - A directory inside the backup_base location

lvm_lvname - Logical Volume name of the backup_base directory (optional)

usb_dir - Directory name to use on USB drive (defaults to backup_dir)

Basic design goals

• Central global settings file at /etc/rsync2usb.conf
• user-level settings file at ~/.rsync2usb.conf
• job specification files at ~/.rsync2usb/*.job
• jobs get run in random ordering (configurable)
• crontab entry should be as simple as /usr/local/bin/rsync2usb
• need an install script to create the symlink in /usr/local/bin
• need an uninstall script to remove the symlink in /usr/local/bin
• check for USB drive running out of space
• automount / encryption is handled by autofs and LUKS, not this package
• use a lock file to control access to USB drive
• allow for multiple backup paths to be specified (one chosen at random)
• needs to work on RHEL5, CentoOS6 and Cygwin64 at a minimum
• depends on the rsync command