Ubuntu Boot Process
I'm a Linux newbie interested in learning more about the computer boot process. I've done a lot of research, but I'm having trouble understanding the process in detail.
What I've learned so far is this, please correct any assumptions I've made.
After a computer does a POST, the BIOS's instruction code (stored as firmware on the computer's motherboard) is executed. The BIOS transfers execution of the boot process to the computer's bootloader, which is found in the master boot record, or the MBR. To do this, the BIOS checks it settings to determine boot order, and will then check the boot device for the MBR. If it is a hard drive, the BIOS checks for partitions. If only one exists, the MBR is found at the beginning of the drive, or sector 0, and is 512 bytes. If multiple partitions exist, the MBR is found in the partition marked active. The MBR will then transfer execution to the kernel, which on a Linux systems executes init as its first process.
Do I understand the process properly? I get a little confused on the master boot record and the volume boot record. What are the differences? My understanding is that the volume boot record exists on each partition's first 512 bytes, but when it is utilized? Is the active partition's first 512 bytes the MBR?
Please help! Thanks in advance.
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