SOLVED need help understaning "System Reserved" and the "page file" partitions on W7


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My W7 Ultimate 64bit system boots from the first two partitions on drive "0" - which is a 2TB 6G/sec hard drive - I was successful in cloning those two partitions from a solid state drive that I originally had on the system. The first partition is labeled "System Reserved" (label assigned by the system), has a drive letter H:, and is marked "System" and Active". The 2nd partition is labeled W7 system C (my label), has drive letter C: and is marked "Boot" and "Page File" (also both are "Healthy" and "Primary Partition").

I tried to clone those two partitions to a new hard drive by copying the individual partitions (using a tool designed for that purpose - rather than cloning the entire 2Tb drive). The location of the copied pair of partitions was not the first partitions on the drive, but they were one right after the other. I made the new "System Reserved" partition "Active", but was not able to assign its partner the drive letter C: from within a running system, nor could I mark it "Boot" or "PageFile". When I removed the original drive and tried to boot to the new drive that housed these two copied partitions (as well as other partitions), a screen came up saying I should run the repair disk, because it couldn't find something it needed.

So - my questions: exactly what is required to make a W7 system bootable?
(i.e., what partitions, and how should they be labeled and marked,what drive letters? and what flexibility is there on their locations?

I can "clone" the entire drive that included the bootable operating system and that works, but what about just moving the required partitions to a new location - on a different drive?

How does one assign the attributes: "Page File" and "Boot"?

Thanks -
 
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catilley1092

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stewl, welcome to the forum! I've never had to allocate space for the "page file" & "boot". Windows does this for you. If you were a Linux user, you would need to partition an amount equal to your RAM for swap, this is the same as the Windows "page file".

With any version of Windows that I've used, I've never had to create & label these things, I've only had to label my data and other storage files. And I do recommend that you create a data partition for storage, docs, VM's, etc. This allows your "C" partition to perform better, and you won't need to defrag as often, either.

Too, if you have your data separate, if you need to reinstall (using a retail, OEM or upgrade disc), you only need to install to your "C" partition, and leave your data intact. You can accomplish this by typing "create and format disk partitions" into the Start Menu, the option will be shown.

You'll need to defrag for best results when shrinking partitions.

As always, and it looks as though you do, it's still important to backup before doing anything.

Cat
 
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Thanks Cat, but my questions were not answered...

Cat - Thank you for replying to my question. Unfortunately, your answer did not give me the information I seek.

I wish to make working (bootable) copies of the two partitions that make up the W7 operating system, and relocate them to a different hard drive (so I can boot from that drive). I can do this with a clone operation, but I'd like to understand what special properties these two partitions have, and what restrictions there are in placing them in different locations. For example, I made a bootable partition of an XP Pro SP3 system on the third hard drive in an older system, and that partition was the 2nd one on that hard drive-yet I can boot it up whenever I want. I just had to moove a copy of the original partition to the desired new location, and it worked. Now, with W7, there are some new factors.

The W7 system assigned the properties "Boot" and "Page File" to the bootable "C:" partition when it created it, but those properties were not passed on when I made a copy of that partition. They are carried along if I make "clone" of the hard drive, but they are lost when just the partition is copied.

My W7 OS has a tiny "System Reserved" partition at the begining of the bootable disk. It has the attribute "System" assigned to it. That attribute is also lost when the partition is copied to another location, but not lost if the entire drive is cloned. I read in one forum that this partition is only created during the W7 install procedure if one choses to have Windows format the disk during the install.

So, again I ask: what are the properties System, Boot and Page File as applied to partitions (i.e., these show up when you look at the drives using the system tool "Disk Manager")? How can I get them assigned to copies of the partitions that I have made? What are the real restrictions on placement of these two files (do they have to be one right after the other? Do they absolutely have to be the first two partitions on the drive? Does it matter what label I have assigned to the partitions?
 

Elmer BeFuddled

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That little bit of system is the windows 7 boot partition. Perhaps someone more up to speed than me will answer this better (correctly!) but I believe that if you install 7 on an already partitioned disc, the separate "system" (boot) partition isn't created and the boot partition is amalgamated into the main 7 partition. You can format the intended partition for 7, but if you format an entire disc the "magic" 100mb/200mb partition will re-appear.

It's been a long time since I clean installed on a fresh disc so that info may be a bit "woolly" if you know what I mean.
 
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clifford_cooley

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The MBR (Master Boot Record) uses a flag to boot to a specific partition. This flag is known as marking a partition active. When booted, Windows will label this partition as the boot partition. The active partition can be changed but the boot partition label will not change until after a re-boot. Warning though if you change the active partition to a partition that does not contain boot files, your system will not boot.

The partition that hold the operating system is known as the system partition. the system partition does not always have to be on the boot partition. Installing Windows to a partition that is not flagged active will divide the two.

The page file partition is simple, this is the partitions that are being used for paging. Changes to which partitions are used for paging can be modified from Advanced System Settings.
 
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The easiest way to deal with this is to boot to the Windows 7 DVD after you copy the System Reserved and operating system partitions and select Repair.

It will then assign the correct attributes to let Windows 7 boot.

Tthe System Reseved partition should be the first partition, since it contains the boot record for Windows 7.
If it is not, the Windows DVD will create a new boot record in the first partition.
 
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Thank you all for the replies.

In the vein of pbcopter's suggestion, I ran the a Windows Repair disk that I made from the working W7 OS that I had copied the partitions from. That DVD disk was able to locate the OS partitions on the new hard drive, even though they were placed more than halfway into the 2 Tb drive-and had other partitions in front of them, and made them become bootable. Note that the repair disk did NOT create a new partition at the front of the disk, but seemes happy with the small "System Reserved" partition that I placed in the middle of the disk. Now I have an exact copy of my original OS running on a new disk. The repair did not make any changes that I can see to any of the installed programs-they are all running perfectly from the new copy of the OS now. That is exactly what I wanted to acomplish.

So a big thanks to you all for the replies.

I still don't understand all the details - like what was required to get that partition that is now running my new copy of the OS - the one that now has an attribute "System" to now have that attribute? What did the repair disk do? And What exactly is inside the "System Reserved" partition (no files are visible)?

But since I now know how to do what I set out to do, knowing those details is no longer very important.
 
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It doesn't creat a new partition, but it does add the boot record to the first partiton.
However, I'm glad it worked out for you.
 

clifford_cooley

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It doesn't creat a new partition, but it does add the boot record to the first partiton.
I don't claim to know everything but I have got to disagree.

I have imaged the first partition and restored it to the second. After changing the second partition to active and rebooted, I've completely removed the first partition without troubles.

The Master Boot Record points the boot process to the active partition not the first partition. Therefor the boot process is not related to the first partition, unless the first partition is marked active.
 
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In my case the first partition appears empty - displays as unallocated space in Disk Manager.

pbcopter - did you mean the first physical partition on the hard drive, or the first of the two that make up the system as we have been discussing (which, in my case is in the middle of the drive)?
 

clifford_cooley

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In my case the first partition appears empty - displays as unallocated space in Disk Manager.
How large is this space?

You might consider using Partition Wizard Home. The wizard will allow you to stretch the partition and make use of this unallocated space.
MiniTool Partition Wizard Home Edition is designated for home user only, to use MiniTool Partition Wizard in a business environment, MiniTool Partition Wizard Professional Edition is required.
 
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I specifically created this small (< 400Mb) partition to see if any of these operations would put something there. Apparently they did not.
I will definately look at the tool you suggest. Always happy to add another good option to my arsenal. Thanks!
 
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I guess I wasn't very clear, sorry. Yes to the first partition of the system.
 
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I laugh (or cry) when I read about how people THINK the computer boots. I am a 35+ year computer engineer - so here goes:

BIOS is told which physical disk to boot (UEFI firmware is different and not explained).
Firmware reads 1st sector on this disk into memory and starts executing its code - sector is the MBR and it contains boot code and the primary partition table. Boot code scans the primary partition table - it contains 4 x 16 byte entries for the one marked ACTIVE. The entry also contains the location on the disk where the partition starts. The MBR code then reads the 1st sector of that partition, called the PBR into memory, and executes it. The MBR knows nothing about OS's; the PBR does. If the ACTIVE partition was formatted by Windows, the PBR will look for a file in its partition called BOOTMGR, load it and pass control to it. Windows calls this partition the SYSTEM PARTITION or SYSTEM RESERVED PARTITION. It contains only the boot files. BOOTMGR reads the BCD which contains the OS entries you can select to boot (multi boot). If there is only one entry, no menu is displayed and the only OS is booted.

In each disk's MBR there is a 4 byte DISK ID - a randomly generated value that is created/written by Windows the first time the disk is inserted. This gives the physical disk a unique identifier.

The BCD entry that is booted contains a reference to the physical disk ID, and to the location of the partition on that disk that contains the OS to boot.

Windows does not allow 2 disks with the same disk ID to be connected at the same time, so when you cloned your partitions, the disk ID was not cloned most probably. In any event, when you booted your cloned system, the BCD had (probably) the wrong disk ID, and if the new locations of the cloned partitions wasn't exactly the same location as the original disk, the partition offset info was also incorrect. So that is why your boot failed.

Startup Repair scanned your cloned disks, found a valid Windows folder, and then determined that disk's ID (physical disk) and the starting offset of the partition it was contained in, and then updated the boot entry in the BCD, so that the next time that entry was selected, it booted correctly.

By the way, I just shake my head when I hear people say that Windows Drive Letters are dependent on which is cabled to the primary, secondary, etc. Nonsense. Each Windows Registry has entries (same as the BCD) that contains the following:

Physical Disk ID + Starting Offset on the disk of the Partition, and its assigned drive letter (or an indicator that this disk and partition are NOT to be assigned a drive letter. This is why:

(a) if you remove a drive from your system for a month and then plug it back in, its partitions get the same drive letters it originally had

(b) if you boot another OS, such as another Windows, or a Recovery Repair, since it is another Windows, and since its Registry has no idea what drive leters were assigned to the target (inactive) Windows, you will see partitions with different drive letters. Drive letters have NOTHING to do with physical. They are only a mapping between a partition that resides (a) on a physical disk (Disk ID in MBR) and a starting offset on that physical disk.

MS wants to get rid of Drive Letters (an ancient artifact from DOS days), but people like them more than Linux Mount Points (concept most people find harder to understand) and software developers keep insisting on MS keeping driver letters. If you go into REGEDIT to hklm\system\MountedDevices, you will see entries \DosDevices\letter:, that have a bunch of hex #'s assigned. These hex #'s are the Physical Disk's DISK ID (unique value in the MBR) and the Partition's Starting Offset on that Physical Disk.

For newbies, the boot process is complicated because as much as computer engineers try to make computers user friendly, they are actually quite complicated. When a computer starts to boot, the software has to start turning a fancy calculator into the computer you love and know. The computer isn't too smart at this point, so the boot process is quite complicated.

I hope this helps those more advanced users.
 
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