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It's been a while since I last bothered with partitioning my hard drive, but now it's time again and I remember last time I did this there was a requirement to put the root partition (or only GRUB?) not behind a certain cylinder number. Is this still the case or could I basically put Linux simply at the end of a drive?

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up vote 20 down vote accepted

That is not a Linux problem, but a BIOS problem, which affects only quite old systems (the first limit was about 504MiB; logical CHS addressing allowed for up to about 8GiB). The BIOS must be capable of using LBA (INT 13h Extensions, defined 1998 with virtually unlimited address space (64 bit)) for Linux to boot from behind 8GiB. There are several versions of LBA but this is a hardware problem, not a BIOS problem (1994, ATA-1: LBA-28, 128GiB; 2003, ATA-6: LBA-48, 128 PiB); a drive will always support the version necessary for its size. I don't know how to check for that support, though (ask your favorite search engine; ask another question here if that doesn't help).

At any rate, that affects only those components which are read by BIOS means. As soon as the kernel (including the modules for disk access) is loaded the Linux drivers are used which do not have this limitation. I.e. on affected systems you must keep all GRUB stages and the kernel and initrd files below this border.

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I see, thanks! It's really been a while since I bothered with this then... – Tobias Kienzler Feb 22 '14 at 20:07
LBA allowed to use large drives (i.e., more than 520 Mb) in its day... – vonbrand Feb 24 '14 at 2:01

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