Larry-
You can modify the restore point storage space as described below by using
the the vssadmin tool from an elevated command prompt. (See Jill Zoeller's
[MSFT] article below:
I believe this explains SR/Shadow Copy--a specific type of Volume shadow
copy space in as much detail as you'll get anywhere:
From Jill Zoeller's [MSFT] blog Windows Server file storage team blog The
Filing Cabinet at
http://blogs.technet.com/filecab
The data is kept in an area called the shadow copy storage area.
http://blogs.technet.com/filecab/ar...used-for-restore-points-in-windows-vista.aspx
"The shadow copy storage area is where shadow copies are stored on each
volume.
The determination of shadow storage size is made when the first shadow copy
is created (typically when System Restore is enabled and creates a restore
point during Setup) and is set to the minimum of 30% of free space or 15% of
the volume. When System Restore is turned on right after Windows Vista is
installed, the shadow copy storage area is most likely to be 15% of volume.
In cases where System Restore is turned on much later, the 30% of free space
formula might kick in, thus limiting the number of shadow copies you'll have
on your system. Also, these percentages don't increase or decrease
dynamically when more (or less) free space is available or after you adjust
the size of the volume...
The amount of change that occurs on the volume determines how large the
shadow copies are and thus how many can fit in the shadow copy storage area.
We don't show the size of individual shadow copies because they rely on each
other, so the size of any one shadow copy is not meaningful."
To store restore points, you need at least 300 megabytes (MB) of free space
on each hard disk that has System Protection turned on. System Restore might
use up to 15 percent of the space on each disk. As the amount of space fills
up with restore points, System Restore will delete older restore points to
make room for new ones.
System Restore will not run on hard disks smaller than 1 gigabyte (GB).
Restore points are saved until the hard disk space System Restore reserves
is filled up. As new restore points are created, old ones are deleted. If
you turn off System Protection (the feature that creates restore points) on
a disk, all restore points are deleted from that disk. When you turn System
Protection back on, new restore points are created.
Also see:
System Restore Beta Chat Transcript (May 19, 2006)
Chat Topic: Live Chat on System Restore!
Date: Friday, May 19, 2006
http://blogs.technet.com/filecab/pages/447166.aspx
Selected chat answers dealing with SR space:
Eduardo [MSFT] (Expert):
A: System restore uses the Volume Shadow Copy Service which manages the
restore points (shadow copies). It will store only a differential copy of
the changed blocks in relation to the files on your disk. This makes it very
efficient in terms of space allocation. The space allocated initially is set
to a max of 15%. Within that space, VSS automatically manages the shadow
copies, and delete old restore points when space is needed.
Dan Stevenson [MSFT] (Expert):
Q: Why there is no fixed maximum age of a restore point ?
A: Because the shadow copy system runs at the disk level. We set aside a
chunk of disk space for tracking changes -- so you could have just 1 restore
point (if you changed many many files) or you could have 60 restore points
(typical usage).
Folkert Bosl [MSFT] (Expert):
Q: When I used System Restore in Windows XP, alot of the time it would fall
back saying "The system could not be restored. Your system has not been
changed". With Windows Vista, is System Restore more reliable?
A: I've done a lot of testing, trying to break SR. Certainly you can manage
that. But it is hard.
If you want to, you can. But when you think of normal usage of an PC it will
be reliable and robust.
The only thing you have to take care of: Don't run too low on
disk-space...doing so and you will loose Restorepoints.
Paul Trunley [MSFT] (Expert):
Q: Can I set restore back further? What's the default?
A: You can restore back to any restore point, older restore points will get
deleted as disk space is needed. There is no fixed maximum age of a restore
point.
Amit [MSFT] (Expert):
Q: When creating a restore point on the system, the files are stored on the
hard drive, therefore reducing the amount of availalbe space. Will there
ever be an option to write restore points to external media such as a DVD
disc?
A: No. You can use CompletePC Backup to image the entire volume to a DVD
disk and do a complete restore if needed.
Eduardo [MSFT] (Expert):
Q: Will System Restore save disk space by mapping common blocks in different
files to one ? i.e. if tho files are somethat or completely similar - will I
get 50% disk space savings in result ?
A: You reference is to single instancing. We don't share common blocks
across files. Instead the Volume Shadow copy Service (VSS) saves off
differential copies at a block level.
Folkert Bosl [MSFT] (Expert):
Q: Folkert Bosl [MSFT] (Expert): Then user or administrator intentionaly
turned off SR - he already made this decision - no needs to ask him this 10
more times in one day then he is installing hotfixes from WindowsUpdate.
Main reason is becouse enviroment is
already managed and other restore means used (like reimaging). SR unable to
address viruses threats and does not guarantee that system will working
after restore - once you will address thouse - this can be reconsidered -
otherwise it's waste of disk space and CPU cycles.
A: I see your point: But if you turn of SR you also turn of the "Previous
Version" feature...certainly if that is also not used....
....that would have to be addressed by our update-engine. Thanks for the
input.
______________________
To turn off SR:
1. Open System by clicking the Start button , clicking Control Panel,
clicking System and Maintenance, and then clicking System.
2. In the left pane, click System Protection. If you are prompted
for an administrator password or confirmation, type the password or provide
confirmation.
3. To turn on System Protection for a hard disk, select the check box
next to the disk, and then click OK.
- or -
To turn off System Protection for a hard disk, clear the check box
next to the disk, and then click OK.
CH
