====== duplicity ======

program for incremental backups tp FTP and scp servers written in python.
often used for backups of (root) servers to FTP spaces in the datacentre.

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===== Bug-Fixes =====

==== restore error 'too many open files' ====

increase open file limits in /etc/security/limits.conf
add:
  root            soft    nofile            4096
  root            hard    nofile            8192

re-login and check:    
  ulimit -Hn
  ulimit -Sn

http://www.cyberciti.biz/faq/linux-increase-the-maximum-number-of-open-files/