Hello,
I still don't have any authoritative kernel links, but this is a good 
summary that I found

"the IDE subsystem in the linux kernel has been functionally replaced by 
the PATA subsystem which uses just that naming convention (sdX instead 
of hdX). IDE is still included in the linux kernel, but is considered 
legacy. However, some distributions still default to IDE."

I'm pretty sure that SL5 is going to continue to use hda instead of 
switch to everything being sda, but I bet that SL6 will be all sda.

I know that Fedora 10 Beta uses the sda only, as does the beta of Ubuntu 
that is currently out.

Troy

John Summerfield wrote:
> Ken Teh wrote:
>> I'm getting confused with the sda/hda naming conventions.  I thought all
>> SATA disks were sd devices.  They were a while back but apparently, not
>> anymore.  And, I can't seem to make any sense of when an sda is an hda.
>> I'm currently installing a system with a SATA system disk that has a IDE
>> CDROM.  A systemrescuecd (Gentoo based kernel) identifies the disk as an
>> sda.  But the 5.2 installer says it's an hda.  There's a single IDE
>> connector on the MB on which hangs a CDROM drive.  Apparently, it's not an
>> hda.  What is it?  An sda?
>>
>> What gives?
>>
> 
> The real answer is, "It depends."
> 
> It depends on which driver is used.
> 
> I have an all SATA system. By default, on SL5 the first drive is hda.
> However, as I recall performance sucked so someone here suggested I tell
> the kernel "hda=noprobe." With this argument, the drive appears as sda.
> 
> On a similar system running Fedora, the first drive is normally sda, and
> I don't know whether I can make it appear as hda without rebuilding the
> kernel.
> 
> I note that the new naming convention is causing problems with somewhat
> randomised naming of drives, particularly when installing with Anaconda.
> 


-- 
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Troy Dawson  [log in to unmask]  (630)840-6468
Fermilab  ComputingDivision/LCSI/CSI DSS Group
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