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Old 10th August 2009
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IdOp IdOp is offline
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Join Date: May 2008
Location: twisting on the daemon's fork(2)
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Quote:
Originally Posted by BSDfan666 View Post
.. an extended partition is essentially a link to an additional partition table that again can have an additional 3 primary, 1 extended partition. (..this can keep going for quite a bit unfortunately.).
These partition tables inside the extended partition will generally define just one usable "logical partition", two empties and a pointer to the next one, so they form a linked list. (My desciption is a bit loose, but that's the gist of it.) The logical partitions can't be used as a primary partition for things that really need a primary partition ... there are just 3 (or 4) of those on the disk in the MBR partition table.

Quote:
OpenBSD 4.5 supports being installed on extended partitions now ...
Interesting, didn't know that or had forgotten!

Quote:
OpenBSD creates "fictitious" disklabel entries for foreign partitions it finds.. but I have not confirmed that it recurses through extended partition tables.

Can anyone comment on this? I never install more then one operating system on my computer.
Yes, I believe that it does. Today I'm running NetBSD and here is my disklabel:

Code:
16 partitions:
#        size    offset     fstype [fsize bsize cpg/sgs]
 a:   5278896  10763550     4.2BSD   2048 16384     0  # (Cyl.  10678*-  15915*)
 b:    263529  16042446       swap                     # (Cyl.  15915*-  16176*)
 c:   5542425  10763550     unused      0     0        # (Cyl.  10678*-  16176*)
 d:  80418240         0     unused      0     0        # (Cyl.      0 -  79779)
 g:    273042        63 Linux Ext2      0     0        # (Cyl.      0*-    270*)
 h:  10490445    273105 Linux Ext2      0     0        # (Cyl.    270*-  10678*)
 i:    626472  16306038 Linux Ext2      0     0        # (Cyl.  16176*-  16798*)
 j:   6313482  16932573 Linux Ext2      0     0        # (Cyl.  16798*-  23061*)
 k:   5943987  23246118 Linux Ext2      0     0        # (Cyl.  23061*-  28958*)
 l:  10506447  29190168 Linux Ext2      0     0        # (Cyl.  28958*-  39381*)
 m:  20370357  39696678 Linux Ext2      0     0        # (Cyl.  39381*-  59590*)
 n:  20338227  60067098 Linux Ext2      0     0        # (Cyl.  59590*-  79767*)
ISTR that OpenBSD can do about the same.

Last edited by IdOp; 10th August 2009 at 03:16 AM. Reason: spelling
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