Re: partitions - primary vs logical and bootability
On Nov 10, 2012, at 2:09 PM, Charles Blair wrote:
I am trying to set up a dual-boot windows 7 / wheezy.
The installer shows me 3 primary ntfs partitions,
presumably for windows7.
I have been able to resize to create freespace.
As I understand it, / must be bootable, which seems
to mean it must be a primary partition. However,
when I do that, the installer shows the remaining
free space as "unusable," and won't let me create
logical partitions for swap, /usr, etc.
I'm sure I'm overlooking something basic. Thanks
for your patient help.
You only get 4 primary partitions. If you want any Logical
partitions, you have to have to make one of the primary partitions an
Extended partition, and put your Logical partitions inside that
So, in effect, your three Primary NTFS partitions have used up all the
primary partitions you can have if you want to use Logical partitions.
As I see it, you have two options:
1) Make your Linux partition an "everything" partition (root, boot,
usr, var, home, and so on...), in Primary slot #4.
2) Backup one of your NTFS partitions (say, #3); put your Linux Root
in the now-free Primary partition (#3) resized as necessary; move the
remaining two NTFS Primary partitions around (if necessary) so you can
consolidate all your free-space into one Extended partition (#4); then
create a Logical partition (#5), inside the Extended (free-space)
partition, to hold the backed-up contents of the old #3; and one or
more Logical partitions (#6, #7, #8) to hold the rest of your Linux
Or... You could leave your old Windows disk alone, buy a new disk and
put Linux on it. Then you can switch between booting Linux and
Windows by using the boot disk chooser of the BIOS. There was a
recent thread in Debian-Users on this topic -- I recommend you read it
before you start.
For more on the topic of Logical/Extended/Primary partitions, see
and the man page for "fdisk" (it may be called "fdisk.distrib" if you
have gnu-fdisk installed) which is available on the web at (among
other places) http://linux.die.net/man/8/fdisk .