This article is from a FAQ concerning SCO operating systems. While some of the information may be applicable to any OS, or any Unix or Linux OS, it may be specific to SCO Xenix, Open There is lots of Linux, Mac OS X and general Unix info elsewhere on this site: Search this site is the best way to find anything.
Basically, they start at 64 (the major device number is 1) and go up by 64 each time you run mkdev hd. Don't expect them to be in the same order as your SCSI IDs for the drives unless that's the order you added them in. Also, if you being running mkdev hd but do not complete the process, it will generally already have assigned the next number; the next time you run mkdev hd, it will add another 64 even though you aren't actually using the last drive you started to create. This isn't a problem; it just looks weird.
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