Craig White craigwhite@azapple.com wrote:

You don't say whether this is hardware or software raid.

I assumed software.

mbr should be put in boot blocks

Being "anal" on terminology, the physical "Master Boot Record" (MBR) in the PC architecture is Cylinder 0 of BIOS disk 80h (first fixed disk).

The traditional name for any boot stream outside of the physical MBR is typically called the "bootstrap" not MBR.

unless you have some other boot manager handling boot and needs to hand off the boot.

And that boot loader goes (at least partially) in the MBR, and then it targets other bootstraps.

On Mon, 2005-08-29 at 10:58 -0700, Robert Hanson wrote:

} ---- } You don't say whether this is hardware or software raid. } } mbr should be put in boot blocks unless you have some other boot manager } handling boot and needs to hand off the boot. } } Craig }

my apologies,

"hardware" RAID5 and noticed i changed the subject, hopefully that does not mess things up for peoples readers etc.

---- unless there's something special about your setup... grub-install to /dev/sda

and yes, one of the things that Brian did assume correctly was /boot should be separately partitioned IF you use LVM - but even if you don't use LVM, it's still much easier to fix things if /boot is on it's own partition.

Brian ;^) thanks for clarifying my incorrect terminology though.

Craig

Robert Hanson roberth@abbacomm.net wrote:

ok, i hear ya. when you get to the point in a CentOS install from CD or DVD it will ask you where you want to put boot or MBR or whatever it says

It asks you how you want LILO or GRUB (newer versions) installed.

So it asks you if you want the MBR-bootstrap combination (disk cylinder 0 plus bootstrap of / or /boot if its separate) or if you just want the bootstrap (of the / or /boot if its separate).

It's very important to note the difference. Especially for those that install multiple OSes -- especially multiple NT or Linux versions.

and i think it gives you two choices. i just got done with an install so i cannot actually see or recall exactly what it says yet something to the effect of and this is off the top of my head and i dont know if it is exact....

Typically says "beginning of disk" (MBR) or "beginning of partition" (bootstrap).

MBR /dev/ida/c0d0 /boot partition /dev/ida/c0d0p1 and that's it.

MBR being cylinder 0 of the disk device.

i always choose MBR as when i have chosen the /boot partition i could never get the machine to boot back up on the final reboot of the unit after install. does this help describe it better?

Craig White craigwhite@azapple.com wrote:

and yes, one of the things that Brian did assume correctly was /boot should be separately partitioned IF you use LVM - but even if you don't use LVM, it's still much easier to

fix

things if /boot is on it's own partition.

I use LVM and put everything under it except / (root).

I typically make 3 primary partitions of equal size (1-8GB), using one (typically /dev/sda3) for / (root). I have a standard 256MB DR-DOS 7.03 image I plop down (typically in /dev/sda1) so I can boot a minimal setup for firmware updates). I leave

Primary partition #4 (/dev/sda4) is the LVM (slice type e8h).

Brian ;^) thanks for clarifying my incorrect terminology though.

Well, I can't exactly call it "incorrect," but it's confusing without following the traditional references. So I was trying to clarify.

On the PC, the "Master Boot Record" (MBR) traditionally means cylinder 0 (512KiB for sectors/heads of 63/16, 8MiB for sectors/heads of 63/255) of the fixed disk targetted as BIOS disk 80h (which GRUB calls hd0).

The "bootstrap" is then sector 0+ of any given slice that is bootable. The concept of a "bootstrap" is commonplace on most architectures for a given OS install.

The concept of the "MBR" as part of the disk is definitely PC/BIOS centric. Other platforms use other methods to transfer control from the firmware to disk. In fact, sometimes the loader that targets bootstraps is in the firmware instead.

Alan Hodgson ahodgson@simkin.ca wrote:

Why not root? Because you don't make a separate /boot? Or so you can boot a non-LVM-aware kernel/initrd? Just curious.

Yes. I also leave 2 other primary slices "just in case." You never know when you have to install a "helper" system to recover the system.

} } Then it doesn't matter one bit. } } I don't even make a separate /boot anymore and haven't in a } long time. I typicaly make a 1-8GB / (root) on my hardware } RAID-1, RAID-10 or RAID-5 volumes. } -- } Bryan J. Smith }

what about any possible security issues for having a separate /boot ??

what about other physical or logical reasons?

i value your input Bryan yet why do people even mention a separate /boot unless it is on an entirely different drive that is only mirrored and not part of the hardware RAID5 for almost obvious reasons...

or a security issue in fstab or something i cant recall right now?

anything else?

thanks and kind regards,

- rh

-- Robert Hanson Abba Communications http://www.abbacomm.net