On Tue, Oct 16, 2007 at 01:54:33PM -0600, Matthew Wilcox wrote: > On Tue, Oct 16, 2007 at 12:54:58PM -0700, david@xxxxxxx wrote: > > On Tue, 16 Oct 2007, Alan Cox wrote: > > >I wouldn't try dividing those by pata v sata. You'll cause all sorts of > > >problems in the process because of PATA-SATA and SATA-PATA bridges. > > > > if you use a PATA-SATA bridge (IDE drive SATA controller), it would look > > to the system like a SATA drive and be addressed and enumerated as SATA. > > But you don't know where the bridge is. It might be on the drive's > board, it might be an explicit enclosure, or it might be on the > motherboard. Each of those scenarios is going to have a different user > expectation. And worse yet, depending on what BIOS options you set at config time, or what might happen after you upgrade the BIOS, whether the drive looks like PATA or SATA could change over time. So if you have /dev/hda hard-coded in your /etc/fstab file, you could and probably will potentially lose after you change a BIOS option or take a BIOS upgrade causing the BIOS configs to get resent and disabling PATA emulation, such that your disk that had previously been /dev/hda now shows up as /dev/sda. (And this is something you will very badly *want* since your disk drive access will be **much** faster once you stop using PATA emulation.) Yet another reason why people who desperately are trying to cling to the good old days of stable device enumerations are going to be disappointed; the *type* of the drive can change over time, even for something as simple as a laptop's primary hard drive, which seem to be some people's favorite example. Unfortunately, people are just going to have to suck it up and get used to a much more complicated world. - Ted - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
