multiple Sata SATAII 150, TX4 - how to tell which drive is which? headaches galore!

[Mitchell Laks <mlaks@verizon.net>]

Dear Experts,

I wanted to ask for any experience with running raid with SATA drives and 
controllers here under linux.

I have been having an interesting time!

I initially tried to use raid1 on  my asus A8v motherboard 
using  a mixture of SATA controllers - 
the built in motherboard SATA controller (via vt8237) 
as well as a  Promise PCI card SATAII 150, 
but had problems with the kernel. My drives gave me all sorts of errors while 
trying to build the  raids and while running mkfs.ext3
and i couldn't  get it to work reliably with the any of the current kernels I 
tried, including 2.6.15.1 the current stable kernel. 
I get countless kernel errors as I mentioned in an earlier post.

Now I have switched to only using the PCI card controllers ( Well, I can put 
multiple controllers into the motherboard). So I use only sata_promise and 
get rid of sata_via, which conflicts (according to my experience). 

Now however, when a drive gives me errors - how can I identify which drive on 
which device is failing? 

The kernel seems to name things randomly.

This is important when a drive 'fails'. Which drive failed? If I am dealing 
with /dev/hda1 /dev/hdb1 /dev/hdc1 /dev/hdd1  on the two ide channels
then  I 'know' which is which.

Even crazier (from an accounting point of view) is  the following.

if I have 2 of these cards, then the sata_promise driver does not appear to 
distinguish "where" (ie: which physical controller port on ___which___ card) 
the drives are. 

The letters don't skip to show you are on a second controller -even if you 
leave blank slots to try to see...
The kernel  randomly  calls the drives sda sdb sdc sdd sde and they seem to be 
anywhere on the physical controllers.  It seems to be completely random. 
HELP!

I since I run a bunch of raid1's, if I get errors I have a major chore. So I 
must stop and reboot countless times doing a binary search using mdadm 
-E /dev/sd[ab]1 |grep UU to find the UUID's of the misbehaving drives.   Then 
look closely at mdadm -E of the 2 final candidates to see which one gave me 
these errors. 

For instance a new drive failed while I was installing the raid, and testing.
To find the erroring drive I had to reproduce the errors each time by  
creating the raids, and running mkfs.ext3 which seems to cause the errors. 
What if the errors were more occult????

Each card had 4 controllers - however when I have more than 1 card it can be 
even more difficult to identify where we are.

Any experience out there to help me?

Thanks,

Mitchell Laks