Script for easy Duplicity backup, suitable for both /etc/cron.daily/ and running by hand.

duplicity-runner.sh

#!/bin/sh
set -e

local=/
remote=s3+http://***/
# figure out correct positional arg order for duplicity
case $1 in
    ''|full|incremental) positional="$local $remote" ;;
    restore|verify) positional="$remote $local" ;;
    *) positional="$remote" ;;
esac

export AWS_ACCESS_KEY_ID=***
export AWS_SECRET_ACCESS_KEY=***
export PASSPHRASE=***

# EXCLUSIONS:
# /dev, /proc, /sys, /tmp, /selinux, /lib/init/rw are meaningless in backups.
# /home/*/tmp is meant to be users' private (not backed up) space

set -x
exec time nice duplicity "${@}" \
    --encrypt-key *** --sign-key *** \
    --full-if-older-than 2W \
    --exclude /dev --exclude /proc --exclude /sys --exclude /tmp \
    --exclude /selinux --exclude /lib/init/rw \
    --exclude /home/\*/tmp \
    $positional