From: dwhodgins@nomail.afraid.org   
      
   On Sat, 10 Feb 2024 05:19:07 -0500, bad sector  wrote:   
      
   > I'm trying to decide on a method to move data between my   
   > Legacy-BIOS desktopo and my EFI laptop. My initial plan   
   > was to use one of the 3.5" drives normally sitting in the   
   > desktop raid tray and connect it in turn to the laptop via   
   > a sata/usb adapter. Looks like a problematic avenue but I   
   > don't wanna buy a usb-portable disk just for this. It's my   
   > first rodeo involving an EFI/Legacy hardware mix and it gets   
   > dizzying, even though I split it into two separate threads :-)   
      
   The question/subject is misleading as this is about partition tables, not   
   about boot firmware.   
      
   Uefi firmware supports using either gpt or mbr partition tables though some   
   badly   
   written firmware requires the boot drive to use a gpt partition table.   
      
   Legacy bios firmware supports using either gpt or mbr partition tables though   
   some   
   very old bios firmware requires the boot drive to use a mbr partition table.   
      
   > Using my Lenovo T480 laptop   
   >   
   > If I do 'fdisk -l' with just a 2tb sata plugged-in via a sata usb adapter   
   > =========================================================================   
   >   
   > # fdisk -l   
   > Disk /dev/nvme0n1: 953.87 GiB, 1024209543168 bytes, 2000409264 sectors   
   > Disk model: SPCC M.2 PCIe SSD   
   > Units: sectors of 1 * 512 = 512 bytes   
   > Sector size (logical/physical): 512 bytes / 512 bytes   
   > I/O size (minimum/optimal): 512 bytes / 512 bytes   
   > Disklabel type: gpt   
   > Disk identifier: 1F5BF8E3-EF76-4A16-BF3E-78B891EAB2B3   
   >   
   > Device               Start        End   Sectors  Size Type   
   > /dev/nvme0n1p1        2048    2099199   2097152    1G EFI System   
   > /dev/nvme0n1p2     2099200   14682111  12582912    6G Linux swap   
   > ...   
   > /dev/nvme0n1p17 1986019328 2000408575  14389248  6.9G Linux filesystem   
   >   
   > *GPT PMBR size mismatch (3907029167 != 488378645) will be corrected by   
   > write*   
      
   I've never seen the GPT PMBR size mismatch before. A search leads to   
   https://arstech.net/gpt-pmbr-size-mismatch/   
   which recommends running "parted -l" and responding with "fix" when asked.   
      
   Do that before continuing to use the drive in either system.   
      
   The sata/usb adapter should work fine in both systems using either a gpt or   
   mbr partition table, since it will not be used as the boot drive.   
      
   Once the existing gpt partition table has been fixed, how is using it   
   problematic?   
      
   Regards, Dave Hodgins   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)