[CentOS] LSI SATA MegaRaid & Centos 7 build 1511

Sat Aug 20 16:21:34 UTC 2016
Lamar Owen <lowen at pari.edu>

On 08/18/2016 02:17 AM, Fawzy Ibrhim wrote:
> I totally agree with John; NEC sold these servers with fakeraid from LSI as I used to login to LSI Firmware to manage the RAID disks.

The NEC compatibility page at 
http://www.nec.com/en/global/prod/express/linux/centos.html indicates 
that the R120b2 is not certified for CentOS 7.  CentOS 5 and 6, yes, but 
not 7.  As there are other servers listed that are certified for CentOS 
7, it isn't that NEC is ignoring CentOS 7; it may just simply not work 
properly on the R120b2. You'll need to file a bug report with Red Hat, 
as CentOS is just going to repackage the source Red Hat ships.

There have been 'zero port' RAID cards in the past where the RAID 
controller uses motherboard ports with hardware RAID; I have an Adaptec 
ASR-2000S here that is for a particular SuperMicro motherboard that uses 
the Adaptec SCSI controllers on the motherboard for the disk ports 
(dedicated PCI-X slot for it; performance was quite good and comparable 
to the RAID controllers with ports on the controller).  I don't know if 
this would be the case with the R120b2 or not.  But it may be that the 
particular MegaRAID controller you have is simply not recognized (maybe 
even shut down after boot) by the CentOS 7 kernel.

For CentOS 7 it would seem that you need to remove the RAID card and 
clear the disks that are on the motherboard ports and install with 
CentOS 7 software RAID.

I know that some older LSI MegaRAID SAS cards are supported; I have 
several Dell PowerEdge 1950's running CentOS 7 (yes, I'm aware of the 
battery issues).  The relevant section of the lspci output on them:
01:00.0 RAID bus controller: LSI Logic / Symbios Logic MegaRAID SAS 1078 
(rev 04)

> But when I install Centos 5.X/6.X 64bit; I can see the disks as standalone disks as well as dmraid devices.
Can you post the output of lspci from CentOS 6, please?  While you might 
not think that lspci would show different outputs from different version 
of the distribution, you might be surprised.