Complete PC Back is generally unusable to me
Posted by admin on May 13th, 2007
I this day and age why would you restrict the image file to write only to DVD and and NTFS FS? Why? There really is no answer. Unless you have a writeable DVD and 30 blank DVDs and/or an drive that you partitioned to NTFS. Then I bet your not even asking the question. But on top of that, no compression? Really no compression? No incrementals?In an effort to make it easy, it is not even close to being usable.
May 18th, 2007 at 09:13 am
Why would you want to write an image file that is going to be larger than 4 gig to a file system that has a 4 gig limitation (fat32)? Regards,Richard Urban MVP Microsoft Windows Shell/User "PJ Nelson" <PJ Nelson@discussions.microsoft.com>
May 22nd, 2007 at 10:44 pm
You didn't mention what type of media you want to back up to if not DVD or NTFS volumes. There are reasons behind why we require NTFS or DVD and there are also differences in the way they are treated:If the target is an NTFS volume, you can do incrementals. The differences are stored as shadow copies within the shadow copy storage area on the volume. The Volume ShadowCopy Service (VSS) is at the heart of these incrementals, and VSS requires NTFS.If the target is an NTFS volume, you cannot compress the .vhd. This has to do with the way in which the VSS service worksbasically on the incremental backup, any compression would lead to huge differences between the current vhd and the one on the shadow copy and we will be deleting old shadow copies at much higher rate. So the backup algorithm is highly optimized to cause as little as possible copyonwrite to be able to keep more backups on the target disk. (See blurb below for additional details on copyoonwrite.)If the target is DVD, then we do compress the .vhd but you can't do incrementals because of the NTFS requirement for VSS.Of course, none of this is obvious from the tool itself, but I wanted to let you know that there are technical reasons behind the requirements. Additional copyonwrite info I mentioned earlier. "Copyonwrite" is Volume ShadowCopy (VSS) terminology. Complete PC Backup uses shadow copies to store the incremental changes to .vhd file. These updates are stored in a hidden area on your hard disk. This area is configurable and can only hold so many shadow copies. Once the area fills, oldest shadow copies are purged. The more changes on the volume, the more quickly those older shadow copies will be purged. From what the developer explained, the act of compressing a .vhd causes it to change more from version to version. We want to avoid having those older shadow copies purged, so we don't compress the .vhd on hard disks.You can find explanations of "copyonwrite" in the Technical Reference at technet2.microsoft.com/WindowsServer/en/library/2b0d2457b7d842c3b6c959c145b7765f1033.mspx?mfr=true. Some internet searching also turns up good hits.Here's a link to our blog for more info on shadow copies: blogs.technet.com/filecab/archive/2006/11/16/identifyinghowmuchdiskspaceisusedforrestorepointsinwindowsvista.aspx. This posting is provided "AS IS" with no warranties, and confers no rights.Want to learn more about Windows file and storage technologies? Visit our team blog at blogs.technet.com/filecab/default.aspx. "PJ Nelson" <PJ Nelson@discussions.microsoft.com>