Apparently, it is not necessary to say that many (if not all absolutely) users have heard that Windows systems have the so-called volume shadow copy service. Of course, far from all ordinary users clearly imagine what kind of tool it is, what it is used for, how to manage it and how to configure it. Meanwhile, there is nothing particularly complicated here. Let's try to consider the shadow copy service of Windows volumes, giving the simplest and most understandable explanation. In principle, despite such a seemingly abstruse name, this tool is familiar to everyone without exception, and many people encounter it quite often when unforeseen crashes or critical errors appear in the system, when automatic or manual start of its recovery is required. But first things first.
What is volume shadow copying in Windows?
Let's start by understanding the essence of this tool, which is available in all the latest systems of the Windows line. To figure out what the volume copy service is, let's try to make some analysis of this phrase, finding out what exactly it can correspond to in the simplest interpretation. Volume refers to a disk or logical partition. This, apparently, everyone knows. As for shadow copy, roughly speaking, it can be interpreted as creating a copy in a mode invisible to the user, often called background.
Thus, it is not difficult to guess that this component is the most common means of creating a backup copy of a disk or partition with preservation in a special reserved area. That is, this is a kind of recovery point from the copy, and this applies not only to the operating system with workable parameters, but also to the saved user files. After all, many noticed that when starting the rollback, not only Windows with programs installed at that time is restored, but also user files.
How it works?
Now a few words about how it all works. The fact is that when the shadow copy service is activated (either in the automatic mode, set by default, or manually), the data is saved in the section for which it is active. In the case of the system partition, it will be saved in it.
There is an invisible area on the disk, intended for placing copies made in it (if you want, some snapshots of the state at a certain moment), for which the operating system itself reserves about three percent of its total volume in the selected section, which, by the way, in most cases taken into account when one of the conditions for the correct operation of the system is the presence of at least five to ten percent of the free space on the system disk.
That is why it is not recommended to clutter the “C” drive, and as a preventive tool, you can regularly use standard disk cleanup, in which when accessing system file actions, you can free up additional free space just by deleting all backup copies (recovery points). As you can already guess, when they are completely cleaned, rolling back the system to some previous state will become impossible.
Along the way, you should pay attention to the moment that when you disable the shadow copy service, you can bring the system to working condition when starting from removable media, if system files are damaged or there is a problem with the bootloader. But recovering user files and previously installed programs will fail.
How practical is it to keep the service active?
Based on the foregoing, it becomes obvious that to quickly restore the system, and programs, and files, you should not disable this component. At least for the system partition - that's for sure. Indeed, in most cases, the main software components of user-installed applications are stored on disk “C” in folders like Program Files and ProgramData. In some cases, even when installing the program in a logical partition, all the same, the main libraries necessary for its operation in the Windows environment are registered in the system partition (of course, only if the application is not portable).
For logical disks, by and large, shadow copying of a volume can be turned off completely painlessly, since they are not related to the operation of the operating system (except for the cases described above). Actually, the whole setup consists only in enabling or disabling this component, as well as indicating for which particular partitions the backup copies will be saved, and how much space will be reserved on the disk or in the partition for saving them (it all depends if you want , from your generosity or greed). However, even when activating shadow volume copying, it is not recommended to excessively get carried away by allocating space for the created snapshots of the disk’s status, because subsequently, when the partition is overfilled, the system will simply have nowhere to save other important data (for example, the same system cache files or cached data of running programs).
How to enable and configure the service in Windows 7 and higher in the simplest way?
Now let's see where the custom options for this toolkit are. The easiest way to access the shadow copy settings in Windows 7 or in any other system is through the computer’s properties, where the system protection item is selected, after which it will be automatically redirected to the corresponding tab.
Here, in a special window, all available currently active disks and partitions will be shown, for which you can view the status of shadow copy a little to the right.
As mentioned earlier, there are not many settings here. After clicking on the corresponding button, you can enable or disable the service for the selected partition, and also use the special slider to increase or decrease the reserved space. You can immediately delete all previously created snapshots (backups).
How to create a recovery point using Windows?
In the main parameters of the protection status, there are also buttons for starting an immediate system recovery and creating a control point in manual mode. Please note that, firstly, after deleting all points for the system partition, rollback will be impossible, and secondly, you can only create a rollback point for the drive or partition for which shadow copying is enabled.
As a rule, the whole process takes just a couple of minutes, and rebooting the computer or laptop after all operations are completed is not required.
How to view all shadow copies and roll back through the command line?
Now we should dwell a little on the issues associated with viewing all the available rollback points, because usually you can choose one of them only at the recovery stage, expanding the entire list. In the system itself, this can also be done, but few of ordinary users know such methods. At the initial stage, if shadow copying of a volume in Windows 7 or in any other OS of this family is enabled, you should go to the command line and run it as administrator (to view points, these rights are not needed, but may be required to restore the system).
To view VSS snapshots (and these are exactly the same backups), you need to register the vssadmin.exe list shadows command, after which all control points will be displayed on each screen, for each of which the time and date of creation, as well as a special identifier will be indicated in braces.
Restoring a system from a desired copy is not so simple. The point here is that first you need to mount a separate virtual drive (disk). For this, the main command vshadows -el = {identifier}, Z is used. In this case, the ID value specified above is entered as an identifier, and Z corresponds to the letter of the created virtual partition. If you need to dismantle the created disk, use the mountvol Z: \ / D command.
Using other Windows tools and optimizer programs
It is clear that many users do not like to work with the command line or do not want to because of the complexity of the tools used. Therefore, to configure shadow copy in Windows, you can use other tools of the system itself, which are no less effective. Not to mention several options for starting a rollback with or without restoring system files, the simplest enable or disable of this tool can be done in the services section (services.msc).
In the editor, you need to find the appropriate service, go to its settings using double-click or the RMB menu, after which, say, to deactivate shadow copying, you need to perform several actions, but be sure to in the following order:
- stop the service by pressing the appropriate button;
- from the list of start modes, select the disabled start type.
After this, again, it is imperative to save the changes in the set parameters, and then perform a complete reboot of the system.
If shadow copy is activated, the actions are performed in the reverse order. But it’s better not to use a standard tool for restoring system parameters, but give preference to the backup and recovery section, where there is a corresponding item.
As for creating shadow (backup) copies or deleting them and starting recovery, for such purposes various kinds of optimizers can be used in which such functions and modules are provided initially.
The CCleaner and Advanced SystemCare utilities proved to be quite good in this respect, in which the creation of control points or the start of rollback is done in a couple of clicks.
Additional management methods
It goes without saying that you can start or disable this service using the settings of group policies or even by changing the corresponding registry keys. However, such a technique for an ordinary user may turn out to be somewhat more complicated than actions with a single service, and digging into the same registry to find the necessary parameters will have to be pretty, and the matter may not be limited to just the main key to activate or turn off the service (for example, You can only delete copies by completely erasing the corresponding records, but finding them can be extremely problematic). But even after deactivating the main service, you will have to start searching for the appropriate files on the disk or in the logical partition to get rid of them yourself. That is why the use of such a manual mode looks extremely cumbersome.
A little distracting from the topic, it is worth mentioning separately that group policies and the registry basically have the same settings, which are duplicated in both editors with different visualizations of the presented parameters. And if it is still possible to refuse to apply the set parameters in the policies at the stage of saving the installed options, then this option is not provided in the registry, since when you exit the editor, the options are saved automatically. In addition, intervention in the system registry without the necessary knowledge can lead to irreversible and catastrophic consequences for the entire system as a whole. Its priority is higher than that of group policies, therefore, changes made to the registry in the policies cannot be returned to their original state (such actions will simply be blocked). So this must be borne in mind.
What should I do if the shadow copy service is not working or gives errors?
Finally, let's dwell on some of the possible problems that may arise in the work of this tool. And let's start with the simplest. The most common error in shadow copying a volume is that the component itself is in an inactive state (either it is disabled in the standard settings, or in the services section, or in policies, or in the registry). As a rule, even under the condition that the registry may contain a key whose value corresponds to the deactivated state of the service, the most common inclusion of this component in the settings described above helps. Also, if the backups have not been deleted, and system recovery may work.
But what should I do if the volume shadow copy service does not work or works, but with obvious failures? It may well be that this problem is due only to the fact that there is not enough space on the disk or in the logical partition to save copies. In this case, we are talking about the fact that the reserved area is full. In this situation, it is advisable to delete those copies that are not needed or the downtime is outdated, and leave only one selected one that contains the necessary operating parameters of the system or links to user programs and files. As already clear, getting rid of all the pictures is extremely undesirable. It is advisable to use such actions only if recovery involves only bringing Windows to life when it is impossible to boot from the removable media, but user applications and files are not taken into account (cannot be restored). Just in case, in order not to remove any important system components, you can use the standard disk cleaning, but in this case, if the option to delete backups is checked, they will be erased all to one. So be careful.
Very often, a shadow copy error, strangely enough, can manifest itself in server versions of Windows if they use SharePoint Foundation components. In this case, the problem may consist in the so-called parallelism of creating copies, when there is a conflict between the real and virtual server, created, for example, using the tools of the Hyper-V module. As one of the simplest solutions, many users call running the vssadmin list writers line in the command console and then rebooting the system two to three times.
If shadow copying of a volume does not work due to problems with the SharePoint Foundation (or rather, with a special service pack) when creating snapshots in SBS 2011, it is recommended to run the special “SharePoint Configuration Wizard” from the Start menu, twice press the continue button, without changing anything in the parameters, and at the end - the “Finish” button. After that, you will need to restart the backup and restart it.
Sometimes, although infrequently, problems with the performance of shadow copy tools can also occur when using SQL server databases. In this situation, as evidenced by the reviews of some users, partial removal of unnecessary or unused databases helps, after which copying starts again in normal mode.
Brief conclusions
So, it's time to take stock of all of the above. Apparently, many have already realized that there is nothing particularly complicated in understanding what the shadow copy toolkit is. Another thing is that immediately questions arise about an unambiguous decision in favor of enabling or disabling this service. Here - at will. But based on practical considerations, it’s better to leave this function of the operating system for the system partition even using standard settings. But for logical partitions, in which only some files can be stored, it can be disabled (in extreme cases, you can always copy the necessary data to some removable media).
As for errors in the operation of the corresponding service, they are extremely rare in user desktop systems and are mostly associated with an unforeseen accidental shutdown of the service responsible for creating backup copies, which can be easily activated even using the simplest methods described above.
And one more remark at the end. If even when the system state backup service is turned on, there are problems with recovery, note that the backup images themselves may be damaged. , , . LiveCD sfc /scannow. , Bootrec.exe :
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