From: forkosh@panix.com   
      
   King Beowulf  wrote:   
   > On Wed, 8 Feb 2023 09:10:12 -0000 (UTC), John Forkosh wrote:   
   >   
   >> I've got a regular old fdisk/lilo-based non-uefi boot drive,   
   >> but the latest (-current64 as of 2/7/23) version created a usb install   
   > ..   
   >   
   > To reiterate and expand on prior comments:   
   >   
   > 1. BIOS must be set to legacy boot, sometime hidden as CSM =ON to allow   
   > legacy boot   
      
   Yeah, I booted into the bios to check, and CSM is indeed ON, as I'd   
   originally left it (and OS is set to "other", etc). But CSM then has   
   some subparameters with three choices: Legacy&UEFI, Legacy-only,   
   UEFI-only. I'd chosen L&U, which seemed to be okay until now,   
   so I reset to L-only, but haven't tried booting the slackware usb   
   stick yet.   
      
   > 2. Slackware DVD and USB installers are hybrid. Hit F11 or F12 (depending   
   > on motherboard) to get a list of bootable devices.   
      
   Wasn't aware of that. I usually boot into the bios, which then has   
   a separate boot menu with those various choices. ...   
      
   > Choose wisely!   
   Isn't that what they told the Captain of the Titanic?   
      
   > You will see 2 entries for the USB stick if the BIOS allows legacy boot   
   > and another for UEFI   
   > NOTE: If legacy is disabled in BIOS, you will only get the UEFI got option   
      
   ... And I think maybe you're right that that's part (maybe all)   
   of the problem. There were two choices for the usb stick,   
   one of which was uefi, and I tried booting the other. But that then   
   just booted the /dev/sda ssd, so I tried several times more until   
   it finally booted the usb stick. But maybe I unintentionally   
   booted the uefi option. I'll have to try some additional experiments,   
   playing with CSM choices and booting the usb install stick.   
      
   > NOTE: Depending on BIOS legacy MBR boot is fallback if no EFI table entry   
   > or partition is found.   
   >   
   > 3. GPT partition can only be legacy booted via MBR on ONLY /dev/sda.   
   > superblock won't work. Use MSDOS partitions, set bootable flag on the   
   > root partition, and then load LILO into root superblock.   
      
   Yeah, my /dev/sda (which is typically reserved for slackware installs)   
   is a 1TB ssd, always <=2TB so I can fdisk it. And running fdisk -l from   
   this new install shows...   
      bash-5.2# fdisk -l /dev/sda   
      Disk /dev/sda: 931.51 GiB, 1000204886016 bytes, 1953525168 sectors   
      Disk model: SanDisk SDSSDH3   
      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: dos   
      Disk identifier: 0xe64e3ed9   
      
      Device     Boot      Start        End   Sectors   Size Id Type   
      /dev/sda1  *          2048  488380780 488378733 232.9G 83 Linux   
      /dev/sda2  *     488382464  976763244 488380781 232.9G 83 Linux   
      /dev/sda3  *     976764928 1465145708 488380781 232.9G 83 Linux   
      /dev/sda4  *    1465147392 1953525167 488377776 232.9G 83 Linux   
   ...so it seems to be okay. Even the newly-installed sda4 is marked   
   bootable, so I guess maybe that  lilo -P ignore  actually did   
   something, despite the warnings.   
      
   > NOTE: GPT does not have partition boot flags   
   > NOTE: you will have to erase the MBR on /dev/sda. legacy boot ALWAYS   
   > looks there 1st.   
   > # dd if=/dev/zero of=/dev/sda bs=446 count=1   
   > (bs=512 deletes the partition MBR+partition table)   
      
   > Have fun!   
   > -kb   
   Thanks a lot for all the very useful information.   
   --   
   John Forkosh  ( mailto:  j@f.com  where j=john and f=forkosh )   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)