Andrew Vong andrewvong@finpress.com wrote:

Dear gurus, Three DELL SC430s were purchased by my company a few months back and I've been told that when they spoke with the DELL representatives, they were informed that these servers were fully RHEL 4.0 compatible. Specs of the servers:-

• Pentium 4 - 2.8 GHz
• 1 GB RAM
• 2x 250GB SATA HDDs

Those specifications are not particularly enlightening. What is more relevant is the system and peripheral interconnect. Namely, in an Intel system, not just the memory controller hub (MCH), but more importantly, the I/O Controller Hub (MCH).

If this is a recent SC430 design, it is most likely the ServerWorks, rebranded Intel, E7230 MCH with the optional 6702 PCI-X hub, with Intel's own ICH7R for SATA, legacy PCI, etc... Which brings me to ...

I tried installing CentOS 4.0 on it but it doesn't seem to be able to detect any hard disks.

The ICH7R is most likely where your issue is.

The ICH5+ has 2 modes, legacy ATA (including SATA) and the Advanced Host Controller Interface (AHCI) mode. I won't go into what AHCI is, but without special OS-side software drivers, it really doesn't give you much. Although there is a lot of work being done on the ICH5+'s AHCI support, I don't trust it myself yet. So you want to disable it, and have the ATA+SATA run in a different mode.

Also, make sure the ICH7R is not configured for FRAID (fake RAID). Although newer DeviceMapper2 (DM2) developments can now read the ICH5+ FRAID organization (at least for RAID-0/1 modes, but probably not the ICH7R's RAID-5, which sucks anyway) and use the Linux kernel's own RAID logic, it's not supported in the stock RHEL4 kernels/user-space packages (and for good reason, long story).

Has anyone out there successfully installed CentOS 4.0 on a Dell SC430? Please help. Your guidance is greatly

appreciated.

I don't know about the SC430, but if it has the 6702 chip with PCI-X, I'd throw a $125 3Ware Escalade 8006-2LP on it. That will get you very reliable, _true_ hardware RAID-1.