Confused about SATA Raid

Sulejmen Mehmedagic smx624 at
Thu Aug 18 07:43:55 GMT 2005

I am not sure if you are still having this problem, but maybe somebody 
else will be able to use the following:

I am using SuperMicro server with Intel ICH5 SATA 150 controller and 
FreeBSD 5.4. As far as I could tell, the trick with SATA RAID is to 
disable/delete RAID in the Intel (after-BIOS) utility, perform one quick 
(because you are going to destroy it anyway) FreeBSD installation, log 
in, and then use the atacontrol utility to create RAID, which you 
already did, according to your post.

After that, you boot from the installation CD-ROM once more, and perform 
final installation ("final" meaning that you should use the time to 
customize it, if necessary). This time, however, you will see ar0 in the 
list of available drives. Choose that one and continue with the 
installation. As far as the installation, I always choose Standard 
(recommended) type at the beginning. However, and I am not 100% sure 
about this, I think that you could benefit from choosing FreeBSD Boot 
Manager, when it comes to that screen (so not the Standard Boot Manager, 
which is selected by default); more about that later.

After looking through several lists I stumbled upon atacontrol utility 
and afterwards using man pages I was able to do the  work I described 
above. However, I was not satisfied completely, since I had trouble not 
with removing one drive and booting (the system would boot with only one 
drive), but after "replacing" (basically inserting the one I just 
removed to mimic drive replacement) that drive back and trying to boot 
again (from this you can see that I remove and add drives only when the 
computer is turned off, if it matters to you or anybody else). At that 
time, I also was not using FreeBSD Boot Manager.

After couple of weeks, I found this article 
which describes the process in similar and more detailed fashion. This 
gave me hope to try one more time and then it was a success. Using 
atacontrol utility and its options (attach, detach, addspare, and 
rebuild) I was able to successfully "replace" both drives and each time 
rebuild the RAID.

The only glitch was in the case when I placed back the second drive, 
i.e. ad6 (which somehow might be the main one) into the server and tried 
to boot. There was a panic message and the server rebooted after couple 
of seconds. Next time, using FreeBSD Boot Manager, I clicked F5 and OS 
booted from a different drive. After logging in, I was again able to 
rebuild the RAID.


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