I have a Gateway (Model DX4850 - Re-branded ACER) that was one of the early adopters of EFI. I don't believe it was UEFI. When I bought it (circa 2012) I wasn't interested in having Microsoft Windows 7 on it at all, so I deleted various partitions and then re-installed it with Ubuntu 12.04. Not knowing about EFI, I believe that I also deleted the EFI partition.
I installed Ubuntu in BIOS mode and many subsequent installations were done in BIOS mode. I have two main partitions for Ubuntu installations (sda1 and sda6), so that my current installation is on one partition and a new installation is put on the other partition. That way, I can continue to work with using my old installation until I get the new installation working properly and my files copied over from the backup.
I noticed that every time I booted, I would get an EFI error and later I noticed that Live CD's and Live USB's detected that it was an EFI motherboard, but would not install in EFI mode. I then realized that I probably had inadvertently deleted the original EFI partition so researched how to restore the EFI partition and created a 200 Mb partition and set the EFI flag.
Now that I had a EFI partition, I installed Ubuntu 16.10 in sda6 in EFI mode. When Ubuntu 17.04 came out, I installed it in sda1 and placed the home folder in a separate partition. However it appeared that the grub files stayed in sda6 and it continued to boot Ubuntu 16.10 until I adjusted the grub menu to boot Ubuntu 17.04 which was item 4 in the menu (I think).
Today I decided to install 17.10 Beta 1 in sda6 and deleted the partition and created two partitions in the space, one for root (/) and one for home (/home). The installation when well, however when it rebooted, it ended up at the grub rescue prompt.
I booted with my Live USB stick, installed boot-repair and tried to fix the problem. I received this message:
An error occurred during the repair.
A new file (~/Boot-Info_2017-09-12__23h48.txt) will open in your text viewer.
In case you still experience boot problem, indicate its content to:
[email protected]
You can now reboot your computer.
Please do not forget to make your BIOS boot on sda (1000GB) disk!
Here is the output from fdisk -l
Disk /dev/loop0: 1.5 GiB, 1553670144 bytes, 3034512 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/sda: 931.5 GiB, 1000204886016 bytes, 1953525168 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: dos
Disk identifier: 0x000df48b
Device Boot Start End Sectors Size Id Type
/dev/sda1 411648 98068479 97656832 46.6G 83 Linux
/dev/sda2 911226878 1953523711 1042296834 497G 5 Extended
/dev/sda3 * 2048 411647 409600 200M ef EFI (FAT-12/16/32)
/dev/sda4 98068480 911224831 813156352 387.8G 83 Linux
/dev/sda5 1936785408 1953523711 16738304 8G 82 Linux swap / Solaris
/dev/sda6 911226880 1008881663 97654784 46.6G 83 Linux
/dev/sda7 1008883712 1936781311 927897600 442.5G 83 Linux
Partition 2 does not start on physical sector boundary.
Partition table entries are not in disk order.
Disk /dev/sdg: 7.5 GiB, 8000110592 bytes, 15625216 sectors
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: 0x1b571474
Device Boot Start End Sectors Size Id Type
/dev/sdg1 * 0 3142655 3142656 1.5G 0 Empty
/dev/sdg2 3118960 3123567 4608 2.3M ef EFI (FAT-12/16/32)
Running:
dmesg | grep -i "EFI"
yields:
[ 0.000000] Command line: BOOT_IMAGE=/casper/vmlinuz.efi file=/cdrom/preseed/ubuntu.seed boot=casper quiet splash ---
[ 0.000000] efi: EFI v2.10 by American Megatrends
[ 0.000000] efi: SMBIOS=0xbad2ed98 ACPI=0xbac2b000 ACPI 2.0=0xbac2b000 MPS=0xfcc20
[ 0.000000] clocksource: refined-jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645519600211568 ns
[ 0.000000] Kernel command line: BOOT_IMAGE=/casper/vmlinuz.efi file=/cdrom/preseed/ubuntu.seed boot=casper quiet splash ---
[ 0.167061] Registered efivars operations
[ 4.965537] efifb: probing for efifb
[ 4.965543] efifb: framebuffer at 0xd0000000, using 1920k, total 1920k
[ 4.965544] efifb: mode is 800x600x32, linelength=3200, pages=1
[ 4.965544] efifb: scrolling: redraw
[ 4.965545] efifb: Truecolor: size=8:8:8:8, shift=24:16:8:0
[ 4.967076] fb0: EFI VGA frame buffer device
[ 5.009887] EFI Variables Facility v0.08 2004-May-17
[ 5.368319] fb: switching to inteldrmfb from EFI VGA
[ 5.963925] tsc: Refined TSC clocksource calibration: 3392.298 MHz
I would like to bring my desktop computer into a properly working EFI system. How do I do this? I have all my files backed up, so I can rebuild everything from scratch if necessary.
UPDATE: I ran:
sudo gdisk /dev/sda1
and got:
GPT fdisk (gdisk) version 1.0.1
Partition table scan:
MBR: MBR only
BSD: not present
APM: not present
GPT: not present
***************************************************************
Found invalid GPT and valid MBR; converting MBR to GPT format
in memory. THIS OPERATION IS POTENTIALLY DESTRUCTIVE! Exit by
typing 'q' if you don't want to convert your MBR partitions
to GPT format!
***************************************************************
Could I allow gdisk to convert the MBR to GPT?
Thank you,
Peter Freeman