[CentOS] Intel DG33BU motherboard

Tue Feb 3 15:15:15 UTC 2009
Paolo Supino <paolo.supino at gmail.com>

Hi William

  You're right ... I do have 2 HDs and my root is not what I thought it is!
Here is what is happening with this system:
It has a SIL SATA RAID0/1 card installed with 2x 160GB SATA HDs connected to
it. The card is configured to mirror between the HDs (RAID1). But as I saw
now Linux actually sees both HDs twice as dmesg shows:
SCSI subsystem initialized
libata version 3.00 loaded.
sata_sil 0000:06:00.0: version 2.3
ACPI: PCI Interrupt 0000:06:00.0[A] -> GSI 21 (level, low) -> IRQ 66
scsi0 : sata_sil
scsi1 : sata_sil
ata1: SATA max UDMA/100 mmio m512 at 0xe0004800 tf 0xe0004880 irq 66
ata2: SATA max UDMA/100 mmio m512 at 0xe0004800 tf 0xe00048c0 irq 66

ata1: SATA link up 1.5 Gbps (SStatus 113 SControl 310)
ata1.00: ATA-7: WDC WD1600AAJS-00PSA0, 05.06H05, max UDMA/133
ata1.00: 312581808 sectors, multi 16: LBA48 NCQ (depth 0/32)
ata1.00: configured for UDMA/100

ata2: SATA link up 1.5 Gbps (SStatus 113 SControl 310)
ata2.00: ATA-7: WDC WD1600AAJS-00PSA0, 05.06H05, max UDMA/133
ata2.00: 312581808 sectors, multi 16: LBA48 NCQ (depth 0/32)
ata2.00: configured for UDMA/100
  Vendor: ATA       Model: WDC WD1600AAJS-0  Rev: 05.0
  Type:   Direct-Access                      ANSI SCSI revision: 05
SCSI device sda: 312581808 512-byte hdwr sectors (160042 MB)
sda: Write Protect is off
sda: Mode Sense: 00 3a 00 00
SCSI device sda: drive cache: write back
SCSI device sda: 312581808 512-byte hdwr sectors (160042 MB)
sda: Write Protect is off
sda: Mode Sense: 00 3a 00 00
SCSI device sda: drive cache: write back
 sda: sda1 sda2 sda3 sda4
sd 0:0:0:0: Attached scsi disk sda
  Vendor: ATA       Model: WDC WD1600AAJS-0  Rev: 05.0
  Type:   Direct-Access                      ANSI SCSI revision: 05
SCSI device sdb: 312581808 512-byte hdwr sectors (160042 MB)
sdb: Write Protect is off
sdb: Mode Sense: 00 3a 00 00
SCSI device sdb: drive cache: write back
SCSI device sdb: 312581808 512-byte hdwr sectors (160042 MB)
sdb: Write Protect is off
sdb: Mode Sense: 00 3a 00 00
SCSI device sdb: drive cache: write back
 sdb: sdb1 sdb2 sdb3 sdb4
sd 1:0:0:0: Attached scsi disk sdb


  /etc/fstab looks for root on /dev/sdb1, while grub looks (and finds) it's
configuration (hd0,0) which corresponds to sda1. The thing that strikes me
is that the mirror works for grub (as it only sees 1 HD),  but doesn't work
for Linux. This defeats the purpose of having a RAID1 to begin with :-(
Unlike your scenario this system was installed from scratch (CentOS is the
only install) and it was done after the mirror was setup in SIL card bios.
BTW: the SIL card boot messages claims that the mirror set is valid and
active. I will hace to check into this.



--
TIA
Paolo
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.centos.org/pipermail/centos/attachments/20090203/d35ebd0c/attachment-0004.html>