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Questions tagged [mbr]

master boot record (MBR)

is a type of boot sector popularized by the IBM Personal Computer.[1] It consists of a sequence of 512 bytes located at the first sector of a data storage device such as a hard disk. MBRs are usually placed on storage devices intended for use with IBM PC-compatible systems.

The MBR may be used for one or more of the following:

Holding the partition table, which describes the four primary partitions of a storage device. In this context the boot sector may also be called a partition sector.

Bootstrapping an operating system. The BIOS built into a PC-compatible computer loads the MBR from the storage device and passes execution to machine code instructions at the beginning of the MBR.

Uniquely identifying individual disk media, with a 32-bit disk signature, even though it may never be used by the operating system.

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What do I select for "GRUB install devices" after an update?

After running Update Manager, a debconf window (titled "Configuring grub-pc"), popped up, requiring me to select the appropriateGRUB install devices for my system. I've made no changes to grub or the filesystem recently, and I don't remember what…
belacqua
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GPT vs MBR. Why not MBR?

I am a Linux user. I don't have Windows on my laptop. Also the hard drive size is less than 2 TB. Then why should I use GPT tables? Can't I go with old fasioned MBR? I will be having two root partitions, two home partitions, and a swap space. So…
daltonfury42
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Is separate EFI boot partition required?

In the past with BIOS, I've never created a separate partition for the bootloader. My question is, if i wish to use UEFI, is a separate boot partition a requirement? PS, I've tried without and it doesn't seem to work. Hence this question.
olfek
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How can I check and change the partition table type?

New computers that ship with Windows 8 also come with a different partition table than before. This along with the move to UEFI causes confusion, as users are unaware of the newer partition table and are trying to install operating systems in legacy…
LiveWireBT
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How to boot into Windows 7 when grub is installed in the Windows partition?

Original title: How can i solve (un)booting windows 7 on the same partition with grub? I've been researching this problem for two to three days but I have came up empty. Basically, partition 1 is Windows 7 and partition 2 is Ubuntu 12.04. I told…
Sim
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Can't boot into Windows 7 EFI GPT after recovery operation

My question, or rather issue, is in the extent of this previous case in which I wanted to grow my Linux (ext4) partition. The partition /dev/sda6 was in the way of doing this and since it contained bios_grub I didn't touch it until someone with…
Nkciy84
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GRUB menu not showing with dual-boot UEFI mode installation

Previously I had Dell Inspiron Laptop with Legacy Boot and MBR disk partitioning with pre-installed Ubuntu 12.04. I needed dual boot with Windows. So I formatted it completely using Live USB, installed new Windows 8.1 and then installed Ubuntu…
user398958
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Fix Windows MBR using Ubuntu Live CD and ms-sys tool

I'm trying to fix the MBR using Ubuntu live CD. I already have the ms-sys installed but from the threads that I saw, I'm not completely sure in which /dev I should execute the command: sudo ms-sys --mbr7 /dev/??? (is it mbr7 the correct option when…
kova
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Convert from EFI to BIOS boot mode

I have a Samsung Notebook NP900X4C with an LUKS encrypted installation on it. The system is booting in UEFI mode. The problem is that the samsung-notebook kernel module is disabled in UEFI mode and due to that I am missing features like the keyboard…
Lukas F.
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How to avoid UEFI? Installation without UEFI? How to have Ubuntu 19, 20, 21, 22 w/o UEFI? Just no more EFI/UEFI problems?

I need to install Ubuntu 19 o. 20 o. 21 o. 22 on a quite recent machine. I enabled all compatibility and legacy modes in BIOS to avoid UEFI. (DO THAT FIRST!!!) I do not want to use UEFI. The installation media (Ubuntu - ISO put on a…
opinion_no9
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How to manually fix a partition table ?

I recently had trouble with the MBR/partition table on my laptop. I managed to rebuild the partition table using testdisk, and install GRUB to get it booting properly again (I'm using a dual-boot with Windows 7). However, I can no longer run gparted…
jwaddell
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How do I dump disk sectors?

I want to see the content of the sector 0 (mbr) of my hard drive. It is possible?
Timofey
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MBR or GPT partition when making ubuntu bootable live usb

I just want to clarify. When making the ubuntu live usb using Rufus, do we select: GPT partition scheme for UEFI MBR partition scheme for UEFI I currently have windows 10 pro installed and would like to make a dual boot system by installing ubuntu…
snookrun
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Difference between Legacy BIOS and UEFI

Why are the terms MBR and GPT associated with Legacy BIOS and UEFI respectively?
burhanuddin abbas
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Unable to install GRUB

Unfortunately (as you can see) I cannot install grub. I have tried /dev/sda as well. Here is my partitioning schema: Troubleshooting + problems: Installed Windows 8 to logical partition (somehow got marked "active") Found Metro BCD to be lacking…
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