Difference between revisions of "Interesting Techniques"

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=== Getting Technical ===
 
=== Getting Technical ===
   
  +
=== rnapshot ===
 
 
==== Dirvish ====
  +
Dirvish takes a similar approach to rsnapshot (see below), but differs in details. A backup regime implemented for one would be difficult to convert to the other.
  +
  +
http://wiki.dirvish.org/DirvishUsage
  +
  +
==== rnapshot ====
  +
 
===== rsnapshot for Linux etc =====
 
rsnapshot is tested on many UNIX-like OS
 
rsnapshot is tested on many UNIX-like OS
#The philosophy behind rsnapshot is tha backups happen regularly and reliably '''only''' if fully automated
+
*The philosophy behind rsnapshot is tha backups happen regularly and reliably '''only''' if fully automated
#*rsnapshot handles the "how, what & where"
+
**rsnapshot handles the "how, what & where"
#*cron handles the "when"
+
**cron handles the "when"
#but wait, there's more
+
*but wait, there's more
#*speed & space efficiency approach that of incremental backups
+
**speed & space efficiency approach that of incremental backups
#*restores files as easily as from stand-alone backup
+
**restores files as easily as from stand-alone backup
#best installed from your Operating System's media/repositories - alternatively
+
*best installed from your Operating System's media/repositories - alternatively
#*http://www.rsnapshot.org/downloads.html
+
**http://www.rsnapshot.org/downloads.html
#'''essential''' - read their HOWTO
+
*'''essential''' - read their HOWTO
  +
==== rsnapshot for MacOSX ====
 
  +
'''Suggested approach:'''
  +
#get installed, configured and working
  +
#*a minimal data set can be configured for test purposes by # ing out many directories listed in the rsnapshot.conf script
  +
#*similarly, a small, surplus hard drive can serve as a test target medium - either internal to PC or via USB interface
  +
#**NB - the default script puts the backup set on a directory of the system disk
  +
#**whilst the simplest, first-stage test that is not a reliable long-term approach
  +
#*backing up manually to an external USB/eSATA drive is a simple, second-stage test
  +
#**could also suffice for data that changes infrequently and is not particularly valuable
  +
#follow HOWTO to automate backups to "local" eg USB drive
  +
#follow HOWTO to backup to LAN or remote drive
  +
  +
'''Storage Requirements:'''
  +
  +
Test/prototype impmentations of rsnapshot/Dirvish could be done from minimal data sets to any available storage media. It is important to accurately estimate the long term storage requirements for production implementations, considering that these tools:
  +
*do not compress the backup
  +
**nor is it practical to do so using supporting tools
  +
*make extensive use of the filesystem function of "hard-links" for space & time efficiency
  +
**it is impractical to later copy/clone file sets containing multiple hard-links to larger media
  +
*run "du" or use a GUI file manager to calculate the size of the data set to be backed up
  +
**have a target medium at least twice that size for data having low rate of change (many home systems ?)
  +
**use yet larger target medium if frequent backups or changes in data are anticipated.
  +
*if multiple backup sets are required (eg local plus off-site)
  +
*#prepare & test a working script ie rsnapshot.conf for one target medium
  +
*#*the backup is readily mountable
  +
*#*it should immediately be readable (being uncompressed)
  +
*#*its lower level directories should accurately reflect that of the source data set
  +
*#give the tested script a unique name, related to the target
  +
*#make a copy of the script to another name
  +
*#*make minor modifications to suit the other target medium
  +
*#**alter "snapshot_root" to reflect possibly different mount point
  +
*#**set "no_create_root 1" for USB medium
  +
*#*test with the other medium
  +
*#routinely run '''each''' script whilst its '''specific''' target medium is mounted
  +
  +
Similar considerations apply to Dirvish
  +
  +
===== rsnapshot for MacOSX =====
 
*might be available for later versions - see:
 
*might be available for later versions - see:
 
http://www.rousette.org.uk/blog/archives/backups-rsync-and-rsnapshot/
 
http://www.rousette.org.uk/blog/archives/backups-rsync-and-rsnapshot/
==== rnapshot for Windows ====
+
===== rnapshot for Windows =====
*probably not feasible because Windows filesystems do not provide the required functions
+
*probably not feasible
  +
**because Windows filesystems do not provide the required functions
 
*cwRsync goes part way
 
*cwRsync goes part way
 
http://www.rsync.net/resources/howto/windows_rsync.html
 
http://www.rsync.net/resources/howto/windows_rsync.html
Line 29: Line 75:
 
--[[Category:Technical Info]]
 
--[[Category:Technical Info]]
   
== Strictly for Geeks ==
+
=== Strictly for Geeks ===
   
 
*
 
*
   
--[[User:Rpeters|Rpeters]]18:10, 24 August 2012 (EST)
+
--[[User:Rpeters|Rpeters]]14:37, 26 August 2012 (EST)
 
 
[[Category:Technical Info]]
 
[[Category:Technical Info]]
 
[[Category:Recommendations]]
 
[[Category:Recommendations]]

Latest revision as of 17:22, 19 November 2016

For General Users


Getting Technical

Dirvish

Dirvish takes a similar approach to rsnapshot (see below), but differs in details. A backup regime implemented for one would be difficult to convert to the other.

http://wiki.dirvish.org/DirvishUsage

rnapshot

rsnapshot for Linux etc

rsnapshot is tested on many UNIX-like OS

  • The philosophy behind rsnapshot is tha backups happen regularly and reliably only if fully automated
    • rsnapshot handles the "how, what & where"
    • cron handles the "when"
  • but wait, there's more
    • speed & space efficiency approach that of incremental backups
    • restores files as easily as from stand-alone backup
  • best installed from your Operating System's media/repositories - alternatively
  • essential - read their HOWTO

Suggested approach:

  1. get installed, configured and working
    • a minimal data set can be configured for test purposes by # ing out many directories listed in the rsnapshot.conf script
    • similarly, a small, surplus hard drive can serve as a test target medium - either internal to PC or via USB interface
      • NB - the default script puts the backup set on a directory of the system disk
      • whilst the simplest, first-stage test that is not a reliable long-term approach
    • backing up manually to an external USB/eSATA drive is a simple, second-stage test
      • could also suffice for data that changes infrequently and is not particularly valuable
  2. follow HOWTO to automate backups to "local" eg USB drive
  3. follow HOWTO to backup to LAN or remote drive

Storage Requirements:

Test/prototype impmentations of rsnapshot/Dirvish could be done from minimal data sets to any available storage media. It is important to accurately estimate the long term storage requirements for production implementations, considering that these tools:

  • do not compress the backup
    • nor is it practical to do so using supporting tools
  • make extensive use of the filesystem function of "hard-links" for space & time efficiency
    • it is impractical to later copy/clone file sets containing multiple hard-links to larger media
  • run "du" or use a GUI file manager to calculate the size of the data set to be backed up
    • have a target medium at least twice that size for data having low rate of change (many home systems ?)
    • use yet larger target medium if frequent backups or changes in data are anticipated.
  • if multiple backup sets are required (eg local plus off-site)
    1. prepare & test a working script ie rsnapshot.conf for one target medium
      • the backup is readily mountable
      • it should immediately be readable (being uncompressed)
      • its lower level directories should accurately reflect that of the source data set
    2. give the tested script a unique name, related to the target
    3. make a copy of the script to another name
      • make minor modifications to suit the other target medium
        • alter "snapshot_root" to reflect possibly different mount point
        • set "no_create_root 1" for USB medium
      • test with the other medium
    4. routinely run each script whilst its specific target medium is mounted

Similar considerations apply to Dirvish

rsnapshot for MacOSX
  • might be available for later versions - see:

http://www.rousette.org.uk/blog/archives/backups-rsync-and-rsnapshot/

rnapshot for Windows
  • probably not feasible
    • because Windows filesystems do not provide the required functions
  • cwRsync goes part way

http://www.rsync.net/resources/howto/windows_rsync.html

-Rpeters13:25, 24 August 2012 (EST) --

Strictly for Geeks

--Rpeters14:37, 26 August 2012 (EST)