On Thu, 2007-08-09 at 18:58 -0500, Mikkel L. Ellertson wrote: > Robert P. J. Day wrote: > > On Thu, 9 Aug 2007, Rick Stevens wrote: > > > >> Uhm, not exactly. You get up to four primary partitions, one of which > >> can be an extended partition. Inside that extended partition you can > >> have as many "logical" partitions as you wish. > > > > i'm not convinced of that infinite limit: > > > > http://www.justlinux.com/forum/showthread.php?threadid=150073 > > > > anyone want to clarify that? > > > From what I understand, there are a max of 16 device entries created > for a SCSI hard drive. (sdx and sdx1 through sdx15) So while you can > have more partitions then that, Linux will not let you access them > when using the SCSI code to access the drive. I believe it is a > driver problem more then a udev problem. Well, the "x" in your example can take the RE form "[a-z]+". For example, we have some storage arrays with, oh, 130 LUNs on them. They appear as /dev/sda[1-15] through /dev/sdiv[1-15] As far as the partition numbers, that's based on the minor number of the block device. The formula is "(16 * drive number) + partition number". The "16" is what limits it to 16 partitions (with partition 0 being the same as the whole drive, e.g. "/dev/sda0" is the same as "/dev/sda"). "man sd" will show you the magic. ---------------------------------------------------------------------- - Rick Stevens, Principal Engineer rstevens@xxxxxxxxxxxx - - CDN Systems, Internap, Inc. http://www.internap.com - - - - To err is human, to moo bovine. - ----------------------------------------------------------------------
