Talk:Shadow Copy

Clarity
This article talks around the nature of VSS without clearly defining it at the get-go. Newcomers to this page - who still and all have the technical chops and more - will be mystified by the meandering language of the first graf. I'd do something about it myself except I came here to learn about VSS and after reading that first graf still don't have a clue.

"Shadow Copy" or "Previous Versions?"
The true name of this feature is Shadow Copy, not Previous Versions. Please see Windows Vista: Features Explained: Shadow Copy for more details. Meteoroid ( talk ) 02:55, 9 February 2007 (UTC)

How to use it in windows xp/2003
There should be a note on how to use it. I was corrected for external linking to this article, but i really wanted to place (the link to) the information in the article, so i could find it again and others could benefit from it and in the future change it to better information. --212.130.183.202 15:27, 30 July 2007 (UTC)
 * Yes, it should be present. But why link when the information can be assimilated into the article? Plus mounting as volumes is not the only way to use VSS. I have plans to do that. But am currently a bit busy. Any help is more than appreciated. :) --soum talk 06:55, 31 July 2007 (UTC)

Style
We should not really write that Shadow Copy is a feature in recent versions of Windows since "recentness" is a relative concept. Please can someone rephrase this section of the article. —Preceding unsigned comment added by 85.189.171.169 (talk) 15:32, 22 November 2007 (UTC)
 * Done. --soum talk 14:13, 23 November 2007 (UTC)

vssadmin Create Commnad
I just tried the vssadmin create command on Windows Vista SP1 and it seems as though the command was removed. Can someone confirm and update the page if that is in fact true? Threesevenths ( talk ) 21:20, 25 March 2009 (UTC)
 * Yes, it is only available on server editions. I have added clarification. —Preceding unsigned comment added by 78.8.147.77 (talk) 14:20, 12 June 2010 (UTC)

Technical Explanation
More technical details are needed on how it works internally. Why is this important? You need to know how it works to understand limitations and how to make best use of the facility.

Maybe I am thick, but I do not understand the point of taking snapshots. Can't the file system store all previous versions of files on the fly? Taking snapshots implies that a complete duplicate of the files are made (since the file system does not know what blocks will later be modified) - but this is obviously incorrect.

I suspect that the snapshot system is used to prevent files that are modified often from clogging up the system with lots of previous blocks (clusters?). So a "snapshot" marks all blocks currently in use as not to be re-used even if freed (deleted or overwritten), but those blocks freed after the snapshots is taken (and blocks already in the free list, of course) can be re-used. —Preceding unsigned comment added by 124.168.144.199 (talk) 02:53, 28 May 2009 (UTC)


 * I agree with with 124.168.144.199 wrote plus the current article is confusing. Can you request a shadow copy a single file or directory or do you shadow copy a volume and from that filter for the file(s) you are interested in? The article mentions being a block level service several times and yet all of the examples are of a file level service? One Microsoft service that uses VSS is Data Protection Manager (DPM) which is apparently able to detect and back up a few blocks that have been modified within a large file. This is very different than old systems where when a file's modified time stamp (or archive bit for even older backup methods) was changed that the backup system made a copy of the entire file. One byte getting changed in a 5gb file meaning the entire 5gb was backed up. DPM with VSS is apparently able to detect which block in the file was modified (the DPM article claims which byte(s)) and to back up just that.


 * Thus there's something about Shadow Copy that this article is not explaining as apparently Windows and NTFS are able to journal a list of modified blocks or possibly byte regions.


 * The article could to a better job of separating out the services that use Shadow Copy, such as Volume Snapshot Service (VSS), Previous Versions, and Shadow Copies for Shared Folders from the core concept of Shadow Copy. --Marc Kupper&#124;talk 23:19, 1 August 2011 (UTC)

files-11
I'm currently on research about this file system. I did hear it did also have his functionality. — Preceding unsigned comment added by 217.194.34.103 (talk) 09:00, September 17, 2009‎

advert
I just added advert on this article, since it doesn't say much about what techniques are used or anything except what's found on Microsoft marketing pages. Can someone fill in with if this uses CoW, how it works, overhead per snapshot and so on? Rkarlsba (talk) 15:06, 6 July 2010 (UTC)

zefir_psv
I've removed the claim that feature has been removed from Win2012 Server. Article reference #10 clearly states that it has been removed only from Win8. — Preceding unsigned comment added by Zefir psv (talk • contribs) 16:51, 17 December 2013 (UTC)
 * Hi. You actually added the claim that it is retained in Windows Server 2012. This needs a source. Best regards, Codename Lisa (talk) 21:09, 17 December 2013 (UTC)

Windows 8
It says "On Windows 8 persistent shadow copies are no longer available."

I'm running Win 8 and I see VSS listed in the services tab of task manager.

So I'm not sure what the quoted sentence means. Jackhammer111 (talk) 16:49, 5 July 2014 (UTC)
 * Hi.


 * I am afraid it appears you have made a set of dangerously wrong assumptions on your own. First, your message suggests you assume "VSS" = "persistent shadow copy". Wrong. The difference between persistent and non-persistent shadow copies are explained at the very top of the History section. Second, if you are not sure what the quoted sentence means, please read the next sentence to find out: "'Therefore the ability to browse, search and/or recover older versions of files via the Previous Versions tab of the Properties dialog of files was removed for local volumes.'"


 * Third, in general, you must not assume every file with the same three-letter name does exactly the same thing, unless you check its publisher, digital signature and installation source.


 * Best regards,
 * Codename Lisa (talk) 06:35, 6 July 2014 (UTC)

3rd Party Software for Shadow Copy Data?
It would be useful to mention whether or not there is a 3rd party (non-Microsoft) software available that gives the User the ability to access the Shadow Copy data outside of Windows.Jonny Quick (talk) 01:04, 22 October 2014 (UTC)
 * Hi. Please define "useful", will you? Best regards, Codename Lisa (talk) 09:53, 22 October 2014 (UTC)
 * I agree with User:Jonny Quick, I think It is important to mention if this capability is exploitable or is exploited by other non-microsoft softwares/drivers that claim or partially claim getting NTFS data readable on their respective platforms, It would also help me to understand the relation between this feature and the fs, as for example the samba part is confusing, as it provides the feature on a different backend fs (non NTFS) that supports snapshots, but at the same time it supports the service API or similar; It'll help clarifying the non-distinction I guess. User:Codename Lisa, I do not understand how your question is constructive ? --Uwe a (talk) 22:50, 20 October 2015 (UTC)

8622colora
Birs 2A02:6680:1106:D35D:C826:C08D:4E8D:B088 (talk) 17:12, 9 October 2022 (UTC)

Ccvchh
Vhfyh 2A02:6680:1106:D35D:C826:C08D:4E8D:B088 (talk) 17:12, 9 October 2022 (UTC)