On Sun, 2007-07-29 at 10:26 -0600, Charles Curley wrote: > On Sun, Jul 29, 2007 at 10:43:50AM -0400, Michael Klinosky wrote: > > I just got another computer, and I'm stalled in the partitioning > > department. I decided to forgo LVM, so I have some questions. > > > > Does it matter in which order I create the partitions? Like, should I > > create /boot first? > > Some BIOSes cannot access beyond a given number of cylinders on a hard > drive. Thus the files to be loaded by the BIOS should be contained > entirely within the range up to that number. If you create /boot > first, you will keep those BIOSes happy, and will not cause any > problems for BIOSes that do not have that restriction. > > > > > On the 'Add partition' window is a checkbox: 'Force to be a primary > > partition'. What's this? (It's not mentioned in the Installation docs.) > > Do any partitions need it? > > This has to do with the history of disk partitioning; it is a kludge > and a bad hack. Even the terminology is atrocious. > > In short, there are four places in the partition table > of the master boot record (the first sector of the hard drive). These > are primary partitions. > > To add more partitions, primary partitions can be relabeled as extended > partitions, which contain logical partitions. Under Mess-DOS, a given > extended partition can have no more than four logical partitions. I > don't know if any other OSs have this restriction. The logical > partition table for each extended partition is contained in the first > sector of the extended partition. You do not put file systems on > extended partitions; they are containers for primary and logical > partitions. > > Thus to add up to four logical partitions, you must sacrifice a > primary partition. But you must have a primary partition to keep older > BIOSes happy (and perhaps current ones; I don't follow BIOS > development closely these days). So you can have up to 13 partitions > in a Mess-DOS compliant hard drive. > > In any case, Linux' libata driver cannot recognize more than 15 > primary and logical partitions, so that sets an upper limit. > > So the only partition you should force to be a primary is /boot, which > should then become /dev/sda1. Let the disk partitioner allocate the > rest between logical and primary. > > The article at http://en.wikipedia.org/wiki/Primary_partition is > pretty good, although it confuses things by conflating primary and > logical partitions. > Great post charles. I had known some of this but had forgotten about it. Regards, Les H
