by Hello,
Is it possible to use Linux Fdisk to create a logical partition
on a MSDOS extended partition?
The reason I need to do this is because my 1.08 GB WD 21000
drive has a primary (bootable) partition with Windoze 95/DOS 7.0.
This primary partition is 256 MB (4k clusters) and everything is
installed and running fine so I do not want to alter this partition.
I would like to have another 256MB dos partition for win 95, and
the remaining .5 GB dedicated to Linux. MSDOS Fdisk won't allow
me to make another primary (msdos) partition. I could make an
256MB extended partition and make all of it a logical DOS partition.
For the rest of the disk, dedicated to Linux, I would be restricted
to only 2 more primary partitions, and I would like more to keep my
filesystems on seperate partitions.
What I could try is create an extended partition (> 256 MB) with msdos
fdisk. Then I could create a logical dos partition of 256 MB on this
partition. The rest of this partition would be made as Linux
logical partitions using Linux Fdisk. I would also be able to create
2 addition Linux primary partitions on the rest of the drive (using
Linux Fdisk). This would allow me to have 2 MSDOS partitions and
more than 2 (3,4,5,..) Linux native partitions. Of course, this
plan of action relies upon the fact that I can create a Linux logical
partition with Linux Fdisk on a DOS extended partition (or could
try vice versa). In other words, I require an extended partition
that has both Linux and MSDOS partitions.
If this could be done, would there be a penalty of using a Linux
Fdisk logical partition on a DOS Fdisk made extended partition?
(performance, reliability, etc...). Also, is there any performance
hit of using extended/logical over a primary (I don't think so).
I hae searched the HOWTO's on this idea of using Linux FDISK to
create a Linux logical partition on an extended partition created
by MSDOS Fdisk, but I have not found much. The closest thing
I have come across was in the Installation HOWTO:
"Note that MS-DOS FDISK will give you an option to create
a ``logical DOS drive''. A logical DOS drive is just a logical
partition on your hard drive. You can install Linux on a logical
partition, but you don't want to create that logical partition
with MS-DOS fdisk. So, if you're currently using a logical
DOS drive, and want to install Linux in its place, you should
delete the logical drive with MS-DOS FDISK, and (later)
create a logical partition for Linux in its place."
In this example, the author suggests that the new Linux partition
could indeed be put on an extended partition created by DOS Fdisk.
I would like to know if this is adviseable. Note I am not referring
to creating a *logical* Linux partition using MSDOS Fdisk as it
is clear this is not to be done. I will ultimately be creating the
Linux logical partition with Linux Fdisk; I just want to put it on an
extended partition that was created using DOS Fdisk.
I appreciate any responses,
--
Paul Colucci
Computational Fluid Dynamics Laboratory
Dept. Mechanical and Aerospace Engineering
State University of New York at Buffalo