Thread: MBR question (XP SP2)
2006-03-23, 14:04 #1
- Join Date
- Jun 2001
- Edinburgh, Midlothian, Scotland
- Thanked 0 Times in 0 Posts
MBR question (XP SP2)
Not sure if this is the right forum, but I use XP, so I'll post here, but if I'm in the wrong place, please let me know.
I've been having some trouble with my McAfee when I subscribed to a new version. As part of the clean-up exercise McAfee's techies got me to do a DOS scan (which found nothing). But it did raise one question with me.##
After completing the scan of each disk, it gives a summary for that disk. The bit that interests me is
Master Boot Records 2
McAfee seems happy with this, but I don't understand why I should have 2 on each disk. (I have 2 physical disks each partitioned into 2 logical drives, giving me a C: D: E: & F: drives). I've searched with Google, but as I got 2.6 million answers, I haven't yet found an explanation.
Without getting too techie, can someone point me at a document that might explain this, and whether there is a problem in having two entries here.
Subscribe to our Windows Secrets Newsletter - It's Free!
Get our unique weekly Newsletter with tips and techniques, how to's and critical updates on Windows 7, Windows 8, Windows XP, Firefox, Internet Explorer, Google, etc. Join our 480,000 subscribers!
+ Get this BONUS — free!
Get the most of Excel! Learn about new features, basics of creating a new spreadsheet and using the infamous Ribbon in the first chapter of Excel 2013: The Missing Manual - Subscribe and download Chapter 1 for free!
2006-03-23, 16:45 #2
- Join Date
- Jun 2002
- Cape Cod, Massachusetts, USA
- Thanked 1 Time in 1 Post
Re: MBR question (XP SP2)
Technically, only partitioned media contains a master boot record; while unpartitioned media only has a boot sector as the first sector. In both cases the BIOS init transfers control to the first sector of the disk after reading it into memory. A legacy MBR contains partition selection code which loads and runs the boot (first) sector of the selected primary partition. That partition boot sector would contain another boot loader. Newer MBRs, however, can directly load the next stage from an arbitrary location on the hard drive. This can pose some problems with dual-booting, as the boot loader whose location is coded into the MBR must be configured to load each operating system. If one operating system must be reinstalled, it may overwrite the MBR such that it will load a different boot loader.
In other words, two HDs, two partitions, two MBRs. Google MBR and it will give you many hits with varying degrees of technical stuff in them.BOB
Long ago, there was a time when men cursed and beat on the ground with sticks. It was called witchcraft.
Today it is called golf!