Some resources for setting up backups:

Comparisons

• wiki documented utilities list: help.ubuntu.com/…

Duplicity

• Create secure remote backups using Duplicity – Tutorial: www.linuxuser.co.uk/…
• Duplicity Backup Howto: help.ubuntu.com/…
• Review: The Duplicity Backup System: everythingsysadmin.com/…

Rsync

• Full System Backup with rsync: wiki.archlinux.org/…

www.cyberciti.biz/hardware/howto-linux-hard-disk-encryption-with-luks-cryptsetup-command/ good how-to

• Manually mounting (will be asked for pass phrase

cryptsetup luksOpen /dev/xvdo syncfs
mount /dev/mapper/syncfs /syncfs

www.linux.org/threads/rhel6-volume-encryption-using-luks.4219/ how to handly re-boot

dd if=/dev/random of=/root/syncfs.k bs=32 count=1
cryptsetup luksAddKey /dev/xvdo /root/syncfs.k
echo "syncfs /dev/xvdo /root/syncfs.k" > /etc/crypttab

• Then add a line in /etc/fstab like:

/dev/mapper/syncfs /syncfs      ext4    defaults

The goal is to sync a common directory structure over multiple sites.

Permissions on server

• create sync user:

useradd -g office -d /home/common -c "btsync service" -m btsync

• Don’t use a sticky bit, or sync will not be able to delete files
• Make sure all contributors to /home/common have primary group office and umask=002
  • This will mean that they all have read/write access to the common files
• Recommended to use the SGID bit to lock all new files with group office and prevent this changing

chgrp -R office /home/common
chmod -R g+s /home/common
chmod -R g+w /home/common

• Note that if a user creates a new file, when btsync replicates it on other systems it will lose ownership information (and be owned by btsync). But because it will have group office it will be editable.

First time setup

There is an excellent article here: www.makeuseof.com/…n-machines/

• Create package list: dpkg --get-selections > ~/packagelist.txt
• Mark packages for reinstallation on new system dpkg --set-selections < ~/packagelist.txt
  • This will mark all packages, but it won’t install them until you run:
• apt-get -u dselect-upgrade

• Cool bash history tips: meandubuntu.wordpress.com/…ps/
• Useful website of Linux/Unix example commands: www.tgunkel.de/…_linux_unix.en
• www.terminally-incoherent.com/… Great bash tips!
• To increase bash history, add HISTSIZE=5000 to your .bashrc file.

Many GTK based apps failed with errors like:

Gtk-WARNING **: Error loading icon: Couldn't recognize the image file format for file '/usr/share/icons/oxygen/16x16/actions/application-exit.png'

until I ran this line to regenerate the cache:

gdk-pixbuf-query-loaders > /usr/lib/x86_64-linux-gnu/gdk-pixbuf-2.0/2.10.0/loaders.cache

This great tool enabled me to recover several hours of work.
I found it from this page: http://www.linuxforu.com/2011/09/recover-deleted-files-in-linux/
All you have to know is the first few bytes of the file and it searches the entire hard drive free space for blocks that begin with those bytes.

Syntax for find

find . -name "*.php" -exec echo {} \;

To find mp3 files after 2009-01-26

touch -t 0901260000 /tmp/t
find /home -newer /tmp/t -name "*.mp3"

To find all text files containing the word “Pressflow”

find /home -name "*.txt" -exec grep -l "Pressflow" {} \;

to chmod all directories to 755 and all files to 644

find . -type f -exec chmod 644 {} \;
find . -type d -exec chmod 755 {} \;

General purpose find script finddate.sh

#!/bin/bash
if [ $# -lt 1 -o "$1" == "--help" ]; then
  echo 'Find files between two dates.

Here is a tutorial: www.rackaid.com/…l-and-how-to/