[lug] SW Raid question

[dio2002 at indra.com]

> The boot failure issue may be present on software RAID.  Older Red Hat
> installs with LILO got this right, but newer ones require you to manually
> go in and install the boot sector on all drives in the array.

I searched hi and lo to find out what i needed to do to get grub to do
this the right way.  And i've found 3 different methods that claim to do
the right thing.  Actually i think all of them work and some do
unnecessary steps simply because folks aren't understanding what the
actual grub commands do.  And i don't blame them because the grub manual
is less than clear.  I haven't actually gotten around to trying any of
them yet because i haven't installed my disks yet ;-)

it's all tied to how the bios labels the disks on reboot.  when one drive
goes down, the working mirror drive moves up in the drive sequence upon
reboot.  so the bootloader needs to handle that.

if you care to share your proven method, i wouldn't complain. :-)

>>2) I can disable bios raid and go with sw raid like initially intended
>
> 2.5) Get another cheap SATA non-RAID card and replace the on-board with
> this.

Now why didn't i think of that :-)... Good plan.  Do you know of any SATA
cards that are plug n play centos 2.6.18 kernel out of the box so i don't
have to scramble looking for and compiling drivers and such to get it to
work?

> I presume you're talking about the 5015M-MT+ system?

That would be correct :-)

> I don't have
> experience with this, but our other Supermicro systems seem to perform
> just
> fine on the discs.  Though, ISTR that they are limited to 100-ish MB/sec
> which makes me think they must be on a slower PCI bus.

This mobo has only ide ata100 support only.  But the sata is sata1 which i
believe is 150mb.