In the days of mbr bios we could save the 512 of the HDD sector. Now is all this gone with UEFI? Is the bootsector of the partition, 512 to 1024 or so bytes no longer valid? IS there specific locations that uefi files are stored in binary of the drive? Or, is that all gone now and we are just looking at files in text in partitions like boot/efi ?
Bill
Once upon a time, Bill Cunningham bill.cu1234@gmail.com said:
In the days of mbr bios we could save the 512 of the HDD sector. Now is all this gone with UEFI? Is the bootsector of the partition, 512 to 1024 or so bytes no longer valid? IS there specific locations that uefi files are stored in binary of the drive? Or, is that all gone now and we are just looking at files in text in partitions like boot/efi ?
UEFI uses GPT partitioning, and uses a partition to store the files needed for booting (which Fedora usually mounts at /boot/efi). The partition has a special assigned GPT type, but is typically a VFAT filesystem.
There's no magic reserved space outside partitions that is used for booting anymore. The firmware finds the device, reads the partition table to find the correct partition, mounts that partition and reads the configured executables from it.
On 9/25/2023 4:44 PM, Chris Adams wrote:
Once upon a time, Bill Cunninghambill.cu1234@gmail.com said: ... There's no magic reserved space outside partitions that is used for booting anymore. The firmware finds the device, reads the partition table to find the correct partition, mounts that partition and reads the configured executables from it.
OK I see, thanks exactly what I was asking. So if for some reason you wanted to save boot code, I guess, you would save partitions and files?
Bill
Once upon a time, Bill Cunningham bill.cu1234@gmail.com said:
On 9/25/2023 4:44 PM, Chris Adams wrote:
Once upon a time, Bill Cunninghambill.cu1234@gmail.com said: ... There's no magic reserved space outside partitions that is used for booting anymore. The firmware finds the device, reads the partition table to find the correct partition, mounts that partition and reads the configured executables from it.
OK I see, thanks exactly what I was asking. So if for some reason you wanted to save boot code, I guess, you would save partitions and files?
Yes. And maybe I guess dump out the EFI boot variables somewhere (output of "efibootmgr").
On 9/25/23 20:44, Chris Adams wrote:
Once upon a time, Bill Cunningham bill.cu1234@gmail.com said:
On 9/25/2023 4:44 PM, Chris Adams wrote:
Once upon a time, Bill Cunninghambill.cu1234@gmail.com said: ... There's no magic reserved space outside partitions that is used for booting anymore. The firmware finds the device, reads the partition table to find the correct partition, mounts that partition and reads the configured executables from it.
OK I see, thanks exactly what I was asking. So if for some reason you wanted to save boot code, I guess, you would save partitions and files?
Yes. And maybe I guess dump out the EFI boot variables somewhere (output of "efibootmgr").
all in /boot/efi, save as a package