Re: [gentoo-user] LiveCD installation not recognizing megaraid RAID set

[Stroller <stroller@stellar.eclipse.co.uk>]

It took Carlos' reply for me to reread & make sense of the original  
post.

On 27 Jul 2009, at 11:46, Carlos wrote:
> Ho-Ki Au a écrit :
>>
>> ... In the BIOS settings, all three disks were added to the  
>> controller for a RAID5 set up. ...  Under /dev, I only saw sda, but  
>> there was no sdb, sdc.  So it looked like there was only one disk  
>> but the system did not recognize it as a raid set.

It looks like *not only* did you add them to the controller, but you  
configured them as a single drive. Therefore this looks correct.

The whole point of RAID is that multiple disks should appear to the  
host o/s as a single drive.

> As mentioned by Neil, dmraid is for software RAID management.  If  
> you want to manage your RAID controller or disk sets from Linux,  
> you'll have to find management software capable of doing this.  Try  
> the server manufacture's site or the RAID manufacture's web site to  
> see if such software exists.


A Google for "PERC5 Linux" reveals:
http://blog.gtuhl.com/2009/03/11/monitoring-dell-perc5-and-perc6-disks-in-arch-linux/

Then searching Portage:

$ eix sys-block/mega
* sys-block/megacli
      Available versions:  ~1.01.40!m!s!t ~2.00.15!m!s!t ~4.00.11!m!s!t
      Homepage:            http://www.lsi.com/
      Description:         LSI Logic MegaRAID Command Line Interface  
management tool

* sys-block/megactl
      Available versions:  ~0.4.1
      Homepage:            http://sourceforge.net/projects/megactl/
      Description:         LSI MegaRAID control utility

* sys-block/megamgr
      Available versions:  ~5.20!m!s!t ~5.20-r1!m!s!t
      Homepage:            http://www.lsi.com
      Description:         LSI Logic MegaRAID Text User Interface  
management tool

* sys-block/megarc
      Available versions:  ~1.11!m!s!t {doc}
      Homepage:            http://www.lsi.com
      Description:         LSI Logic MegaRAID Text User Interface  
management tool

Found 4 matches.
$

Viewing the RAID using the correct LSI utility should show the  
individual drives.

I use the tw_cli for my 3ware controller. This is how it it appears on  
my system (the LSI utility will have a different name & syntax):

$ sudo tw_cli /c0/u1 show
Unit     UnitType  Status         %RCmpl  %V/I/M  Port  Stripe  Size(GB)
------------------------------------------------------------------------
u1       RAID-5    OK             -       -       -     64K     931.303
u1-0     DISK      OK             -       -       p4    -       465.651
u1-1     DISK      OK             -       -       p5    -       465.651
u1-2     DISK      OK             -       -       p6    -       465.651
$

Stroller.