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   alt.os.linux      Getting to be as bloated as Windows!      107,822 messages   

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   Message 107,196 of 107,822   
   Paul to bad sector   
   Re: migrate triple-booting legacy-BIOS L   
   23 Apr 25 09:38:18   
   
   [continued from previous message]   
      
   > If I knew what got changed I could maybe try to fix it before beginning all   
   over but as it is I don't even have a working legacy BIOS departure point any   
   more :-(   
   >   
   > BTW, having made several w10 freshies, I found the USB installers made with   
   the WoeUSB linux utility fairly good AND persistent. The one made by the MS   
   uti (on my laptop 'for another computer' which is my only windows also box)   
   never worked at all, and    
   the ones made with Ventoy got invariably destroyed for each 2nd attempt (see   
   prompt blowup in image).   
   >   
   > https://imgur.com/59mcvHC   
   >   
   >   
      
   The boot menu is in a file called "BCD". The internal format is "registry file"   
   but that never comes up when using tools to work on it. I mention that in case   
   your hex editor examination shows "binary" and you are wondering why it is   
   binary   
   inside. They used a registry format, as a storage format for small objects.   
      
   It takes somewhere on the order of four specific commands, to make a brand new   
   BCD file appear before your eyes. But because there are other files that   
   are typically nearby, we don't usually "start from scratch" all that often.   
      
   Instead, we're looking for the directory where that is located, and   
   doing something to augment the file.   
      
       bcdedit                        # Dump the BCD file that the system booted   
   with (good when OS is working)   
      
       bcdedit /store C:\boot\BCD     # Dump the BCD file from selected location   
   (while using install DVD to do maintenance)   
      
   Here are two pictures showing the Legacy and UEFI boot devices I have on the   
   other machine.   
   I'm showing these pictures, as the partition structure is a bit less noisy.   
      
      [Picture]   
      
       https://i.postimg.cc/7L4JqvX0/legacy-boot-example.gif   
      
      [Picture]   
      
       https://i.postimg.cc/zGZVkms6/UEFI-boot-example.gif   
      
   As an example of a "thing" you would do with bcdedit while   
   the OS is running, these kinds of commands set the OS description   
   in the on-screen boot menu, early in boot. The "identifier",   
   can be spotted when you use the "bcdedit" command without parameters.   
   and the "identifier" is context sensitive. It may appear with   
   a different value when you are booted using a Windows installer DVD   
   and the Troubleshooting Command Prompt window.   
      
   bcdedit /set {current} description "Windows 10"   
   bcdedit /set {default} description "Windows 10"   
      
   If I was booted from the DVD, I would do them similar to this. The boot DVD,   
   X: is the system partition.   
   Leaving C: available as a letter for this sort of repair activity. Notice when   
   I am using the DVD   
   like this, I have to "know my stuff" to target the correct BCD file.   
      
   bcdedit /store C:\boot\BCD   /set {current} description "Windows 10"   
   bcdedit /store C:\boot\BCD   /set {default} description "Windows 10"   
      
   *******   
      
   General rules of thumb (you know these already):   
      
   1) Since "usually", the dependencies of an OS are on a single disk drive,   
      it makes the most sense to have boot material for it, right on that same   
   drive.   
      This allows BIOS steering to the drive, if and when needed, for emergencies.   
      
   2) You are certainly allowed to have a boot manager on disk 1, and jump over   
      to disk 2, using GUIDs or UUID or identifiers of that sort. But you also   
      want whatever OSes on disk 1, to be bootable from the disk 1 boot materials.   
      
   3) This means, the BIOS could point at disk 1 for "machine-wide" boot, or   
      the BIOS could point to disk 2 for "disk 2 specific boot". There can be   
      a boot menu on disk 1 and disk 2. The only time this gets confusing,   
      is when you do "sudo update-grub", and there could be the odd surprise   
      depending on the configuration.   
      
   If I was in the room, the Windows disk with the boot problem, first   
   we'd have to figure out whether the recommended rules were followed   
   ("only have the disk receiving an install, connected during the install").   
   If that was the case, then repairing the boot-ability, could again   
   be performed on the single disk.   
      
   You will notice in my picture, I used "diskmgmt.msc" to display the   
   disk setup in Windows. And the labels hint where key materials have gone.   
   If "System", "Boot", and optionally "Active" are smeared over the two   
   disks, this presents some challenges, and you have to decide what   
   you want to do as a Wizard. You can move some of the materials around.   
   I've done that a couple times, when something was in an awful mess.   
   The purpose of moving the items, would be to try to get all those   
   key identifiers lit up on the one disk.   
      
   I can't go much further than that, as with a non-booting system, even if   
   we cable up the two forensic project disks to a third Windows system disk.   
   the booted Windows will only show its own identifiers and not where   
   everything is smeared on the other two disks. It's going to be   
   a challenge to figure this out. By dumping the BCD file, there could   
   be hints where the BCD is pointing. But again, no guarantees. It's all   
   a bit of a puzzle at times, that's for sure.   
      
   *******   
      
   Preparing Macrium Reflect "Rescue CD", starts with the installer.   
   I need some odds and ends to do a demo, so I'll try to post later.   
   If your maintenance OS was 64-bit, you could use the 64-bit one.   
   The reason for using the 32-bit one, is when booted from that,   
   a small number of GUI-oriented win32 programs will run under that   
   environment, which can be useful at forensics time.   
      
      https://download.macrium.com/reflect/v7/v7.3.6284/reflect_setup_free_x64.exe   
      
      Name: reflect_setup_free_x64.exe   
      Size: 115,719,576 bytes (110 MiB)   
      SHA1: B6724C7B6F5AF146406FAAA78F845A6C281D67D8   
      
      There is also a 32-bit one. For 32-bit setups.   
      
      https://download.macrium.com/reflect/v7/v7.3.6284/reflect_setup_free_x86.exe   
      
      Paul   
      
   --- SoupGate-DOS v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)   

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