Musings of a Web Technologist
Here’s a handy command to display the Internet facing IP on a Unix/Linux command line. This is particularly useful on systems where lynx is not available, and where the system might be behind a firewall so that the public IP cannot be discerned from ifconfig output.
curl -s myip.dk | grep 'IP Address' | egrep -o '[0-9.]{3,}+'
A FreeBSD shell script to dump filesystems with full, and automatically incremented incremental backups to a given directory location.
I wanted to automate filesystem dumps on my servers running FreeBSD 7.2. After some searching I came across Vivek Gite’s FreeBSD Full / Incremental Tape Backup Shell Script which gave me a lot of ideas. Since I’m not using tape as the backup target I wanted to make a script specifically for that purpose while at the same time improve handling of some error conditions (such as, most importantly, checking for a missing level 0 dump before proceeding with an incremental dump) and add some new features such as autoincrement the dump level so that the dump level is not tied to specific day of the week.
Here’s my version of the script. While it bears some resemblance to Vivek’s script, it is largely rewritten. Read the script header for more information.
NOTE! In his comment James pointed out a possible bug in the script. The displayed script indeed had a problem: it was missing a backslash in front of the first dollar sign at:
eval “local fspath=$${fsname}path”
This was caused by the script display plugin in WordPress that treated the backslash as an escape character (this has now been fixed). To be on the safe side, please download the script as a tarball. To further validate the integrity of the tarball, it should produce a md5 hash of 732ac44f11ba4484be4568e84929bb6a.
#!/bin/sh
# Autodump 1.5a (released 01 August 2009)
# Copyright (c) 2009 Ville Walveranta
#
# A FreeBSD shell script to dump filesystems with full, and automatically
# incremented incremental backups to a given directory location; this script
# was written with the intent of saving the filesystem dumps not onto a tape
# device but on another hard drive such as a different filesystem on the same
# computer. The resulting dump files can be copied offsite with a separate
# cron job.
#
# This script creates the necessary directory structure below the defined
# 'BASEDIR' as well as the necessary log file. This script also ensures that
# the level 0 dump exists before creating an incremental dump; if it doesn't
# the script automatically erases the incremental files for the current week
# (if any exist) and starts over with a level 0 dump. This way you can start
# using the script on any day of the week and level 0 dump is automatically
# created on the first run.
#
# When ran daily (such as from a cron job), the script creates level 0 dump
# on every Monday (beginning the ISO week), or Sunday (beginning of the U.S.
# week) and an incremental dump on all the other days of each week. The dumps
# are compressed with gzip and saved below the 'BASEDIR' to an automatically
# created directory whose name is derived from the list given in 'FSNAMES'.
# Each week's dumps are organized into subfolders with name YYYY-WW ('WW'
# being the current week). By default three most recent weekly dumps
# (level 0 + incrementals) are retained.
#
# The script maintains each weekly folder's date at the _beginning_ date
# of the dump (i.e. Monday or Sunday of the current week) at 00:00, not
# at the most recent incremental's date/time.
#
# By default the root (/) and usr (/usr) filesystems are dumped. To add more
# add a "friendly name" to the 'FSNAMES' list (it is used for the weekly folder
# names, for dump filenames, and to reference the corresponding mount point
# variable); then add the corresponding mount point variable (i.e. if you
# add "var" to 'FSNAMES', then add a variable varpath=/var). The "path"
# ending of the mount point variable name is required.
#
# Since the number of incremental dumps is limited to nine (level 0 +
# incremental levels 1-9), the script will allow maximum of one dump
# to be created per day. However, since the level incrementing is dynamic
# you can start the script on any day of the week, and run it on any
# number of days during the rest of the week and you'll always get
# level 0 plus the incremental dumps in sequential order. However, The
# new weekly folder is always created on Monday or Sunday (as chosen by
# you). Note that the script determines whether "today's" dump exists
# based on the modification date stamp of the most recent dump. Hence
# it is a good idea to run this script in the early hours of each day
# rather than in the very end of each day. Running the script, for
# example, at 23:50 has the potential to push longer dump processes
# over the midnight and so potentially cause the next day's dump to
# be skipped.
#
# Written for FreeBSD 7.2 but should work on most BSD and *NIX systems with
# minor modifications.
# -------------------------------------------------------------------------
# Copyright (c) 2009 Ville Walveranta
#
# This script is licensed under GNU GPL version 2.0 or above, and is provided
# 'as-is' with no warranty which is to say that I'm not liable if it wipes out
# your hard drive clean or doesn't back up your precious data. However, to the
# best or my knowledge it is working as expected -- I'm using it myself. :-)
# -------------------------------------------------------------------------
# This script was inspired by
# FreeBSD Full / Incremental Tape Backup Shell Script
# by nixCraft project / Vivek Gite
# at
I needed to restore some files from an archive on UNIX, but only the files of a particular date-range were needed. It took a few moments to find and figure out how I could easily extract files older than a particular date, or files from a particular date-range. This is how:
Likewise, for a range of dates:
NOTE: For an even easier way to accomplish the same, see comment by Hampus below!