Cloned OS from HDD to SSD; good install? Have doubts

In my post #21, can somebody explain what each of the five partitions is for? Think I get 3 (Windows); 4 (Windows Recovery) & 5 (Dell Recovery); is this correct? What is 1 (ESP) and 2 (?)? Why did Dell not follow the recommended partition order?

I did re-size the Windows partition smaller. I'd rather not mess around with this again unless I have to but now am wondering as post #27 says re-sizing is a concern if WinRE and system recovery image are partitions 4 & 5. But MS then kind of contradicts itself by leaving the Recovery Image last.

Partitions 1 & 2 are essential partitions for a UEFI system to boot. Please leave them alone or your PC may not boot! For example see https://msdn.microsoft.com/en-us/lib...(v=vs.85).aspx

BIC said:

In my post #21, can somebody explain what each of the five partitions is for? Think I get 3 (Windows); 4 (Windows Recovery) & 5 (Dell Recovery); is this correct? What is 1 (ESP) and 2 (?)? Why did Dell not follow the recommended partition order?

I did re-size the Windows partition smaller. I'd rather not mess around with this again unless I have to but now am wondering as post #27 says re-sizing is a concern if WinRE and system recovery image are partitions 4 & 5. But MS then kind of contradicts itself by leaving the Recovery Image last.

OK, I'll have a stab at answering you without getting too sidetracked hopefully...

ESP Partition

The minimum partitions required for an EFI system to boot is 1. This partition is variously called EFI, ESP (EFI System Partition) or System. It doesn't matter where it is on the disk - it used to be the first (as it is with you) but with Windows it is now (generally) in position 2 (by default but not always and it doesn't have to be).

On an EFI computer the firmware will look for a partition of the correct type (this hex code EF00), formatted FAT and being at least 100MB in size. Generally it doesn't contain the OS as well (and for windows it can't as it has to be formatted FAT and Windows must be installed on NTFS).

Inside the ESP is a directory /EFI containing subdirectories /BOOT or /Microsoft or /Apple or whatever which tell it what sort of partition type and program to call to boot the OS. You can see which EFI bootloader will be used by looking at bcdboot /enum {bootmgr} command in Windows

Code:

C:\WINDOWS\system32>bcdedit /enum {bootmgr}

Windows Boot Manager
--------------------
identifier              {bootmgr}
device                  partition=J:
path                    EFI/Microsoft/BOOT/bootmgfw.efi
description             Windows Boot Manager
locale                  en-US
inherit                 {globalsettings}
default                 {current}
resumeobject            {9c34aef1-9152-11e5-9c76-00155d013517}
displayorder            {current}
                        {2bd3fb00-6091-11e5-86c4-c3a22c898ce3}
                        {2bd3fafe-6091-11e5-86c4-c3a22c898ce3}

This path is either held in NVRAM or figured out by the firmware. This is the best description I can find efi bootloaders principles.html

C Partition

For Windows you need at least one more partition, the C primary partition which must be formatted NTFS and have a type code of 0700. This can be before or after the ESP but normally is after. The Windows bootloader program in the /EFI partition in the ESP will then just go ahead and startup Windows from here. Other bootloaders may display a menu instead asking whether to load Windows or Linux or whatever.

MSR Partition

Microsoft also recommend a Microsoft Reserved Partition which according to their documentation is 128MB (but in my recent tests it is created as 16MB). This is a hidden partition type 0c01, is not formatted and is supposed to come before the C partition (wherever that is). The purpose of this partition is a little vague to me. Microsoft says it is for future use or to enable resizing partitions. Some other file systems (eg OSX) also require empty space between partitions.

I'm not sure as resizing partitions (and Windows in general) works perfectly fine without it. However they recommend it so I leave it. Microsoft Reserved Partition - Wikipedia, the free encyclopedia.

RE Tools

This is optional (unless you want to use bitlocker drive encryption in which case it must exist). The Windows RE partiton is a hidden partition type 2700, format NTFS and can be anywhere on the disk (although as mentioned earlier MS recommend it is first). If it doesn't exist when you clean install Windows it will either be created with a size of about 450MB (if you delete all partitions) or the recovery environment files will be placed on the C:\ drive. You can see where the WinRE is located by looking at the reagentc /info command.

Code:

C:\WINDOWS\system32>reagentc /info
Windows Recovery Environment (Windows RE) and system reset configuration
Information:

    Windows RE status:         Enabled
    Windows RE location:       \\?\GLOBALROOT\device\harddisk0\partition1\Recovery\WindowsRE
    Boot Configuration Data (BCD) identifier: 9c34aef3-9152-11e5-9c76-00155d013517
    Recovery image location:
    Recovery image index:      0
    Custom image location:
    Custom image index:        0

If it exists it will contain the registered WinRE image and (if applicable) the programs required for pre-boot bitlocker encryption.

OEM Recovery

This is optional and contains an image to allow reset to factory state. I've never had a PC with this partition so I've no clue about it except it is another hidden NTFS formatted type 2700 partition which must be large enough to hold whatever the OEM thought was required to restore Windows.

Why the order matters

Honestly it doesn't. Most of the partitions are not even required and when they are they are always defined either by their type (ESP, Primary C drive) or explicitly (WinRE).

The arguement MS are making with their suggested layout is that perhaps you might want to delete your dell OEM recovery partition. If you have WinRE partition stuck just after C you can't extend C to take this space without moving it.

Why did Dell ignore this and put RE there? Who knows? Perhaps they think it is neater to have ESP at the start. Perhaps they didn't read the recommendations. Perhaps they want to discourage people deleting their recovery partition.

My partiton layout is like this (there is 128MB unallocated between 5 and 6). Whenever I use any Windows tool to resize 4 (my C drive) and 5 (Shared Data) it resets the type code of partition 6 to 0700. This happens with disk management, Minitool partition wizard etc. Could be there is some sort of bug there which is why they want the WinRE earlier...

Code:

Number  Start (sector)    End (sector)  Size       Code  Name
   1              40         1024039   500.0 MiB   2700  Windows RE
   2         1024040         1433639   200.0 MiB   EF00  EFI
   3         1435648         1468415   16.0 MiB    0C01  Microsoft reserved ...
   4         1468416        49500159   22.9 GiB    0700  Basic data partition
   5        49501912       186482799   65.3 GiB    0700  Shared
   6       186482800       235708599   23.5 GiB    AF00  El Capitan
   7       235708600       236978135   619.9 MiB   AB00  Recovery HD

In any case it really doesn't matter - you can leave your layout as it is until you need to change it and then put it in any order you find pleasing. If you have HDD it might be a bit quicker to have C towards the left (if you had a big data partition as well. If you have SSD it makes not difference at all.

You can shrink C and make a new partitions next to it now with no problems. What you can't do is delete partition 5 and extend C to use its space without moving partition 4 (RE) somewhere first.

lx07 said:

In any case it really doesn't matter - you can leave your layout as it is until you need to change it and then put it in any order you find pleasing. If you have HDD it might be a bit quicker to have C towards the left (if you had a big data partition as well. If you have SSD it makes not difference at all.

You can shrink C and make a new partitions next to it now with no problems. What you can't do is delete partition 5 and extend C to use its space without moving partition 4 (RE) somewhere first.

Thank you for that detailed and reasonably easy to understand explanation and particularly for your bottom line summary. Also, thanks to all that responded, I learned a lot from this thread (my first one on this forum). I had asked this question on another forum and got some OK answers, but did way better over here.