Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 17 Dec 2009 07:33:58 +0800
From:      Fbsd1 <fbsd1@a1poweruser.com>
To:        FreeBSD Questions <freebsd-questions@freebsd.org>
Subject:   is this booting info correct?
Message-ID:  <4B296E66.6030405@a1poweruser.com>

next in thread | raw e-mail | index | archive | help
Users with Microsoft/Windows knowledge of how a hard drive is configured
may have a terminology issue with FreeBSD. Microsoft/Windows and FreeBSD
use the word partition to mean different (but related) things.

FreeBSD and Microsoft/Windows have primary-partitions, but they call
them different things. FreeBSD calls the Microsoft/Windows
primary-partition a slice.

The number of hard drive primary-partitions/slices is determined by the
motherboard BIOS (Basic input output system), not the operating system.
Standard motherboard BIOS limits hard-drives to 4 main divisions

Each of those are called primary-partitions in Microsoft/Windows
terminology and slices in FreeBSD terminology.

Each primary-partition/slice can be sub-divided into smaller chunks. In
Microsoft/Windows, they are called extended-partitions. They are
implemented very differently and are not compatible with FreeBSD. In
FreeBSD the sub-divisions are called partitions.

Each one of the 4 max primary-partitions/slices can be made bootable.
The first physical track of the allocated space of each
primary-partition/slice has an initial sector (512 byte block) that is
called the boot sector. If it contains boot up code the motherboard BIOS
considers it to be bootable.

Each physical hard drive in the PC has it's own MBR (Master Boot
Record). The MBR is located in sector-0 of the first physical track on
the hard drive. The standard MBR in Microsoft/Windows and FreeBSD
defaults to booting the first primary-partition/slice allocated on the
first hard drive cabled to the PC.

There are MBR booting programs that you can load into the MBR on the
first physical cabled hard drive to scan for other bootable
primary-partitions/slices on this hard drive and any other hard drives
cabled to the PC. It displays a menu giving you the option to choose
which one you want to boot from. This gives you the ability to have more
that one operating system installed on your PC at one time.











Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?4B296E66.6030405>