Convert Software RAID to RAID 5 on PowerEdge 1750

Question

I inherited a pair of PowerEdge 1750 servers. One of them is using hardware RAID 5 with a PERC 4/DI and it seems to be working correctly... I might have to update its version of OpenManage along with the drivers and firmware, but that's not critical right now.   The other PowerEdge is doing RAID 1 in software -- Windows Server sees two physical 'dynamic' disks on an LSI Logic SCSI adapter and it's using dynamic disks to do the mirroring. This is the machine I want to convert to hardware RAID 5. I have no clue why it's in software RAID right now, but I'd rather stop doing that.   On the surface, the machine doing RAID 1 in software is physically the same.  It has three slots for SCSI SCA hard drives. I haven't poked in the BIOS on there yet, so I don't know how simple it is to switch the internal SCSI from 'normal' to 'RAID' mode yet. Once that's done though, I'd still need to rebuild the system on the new RAID array.   First off, what would it take to change this machine from 'normal' mode to RAID mode? Once there, I'm sure I can use the OpenManage software to build a RAID array. And second, is there a way to preserve my OS installation while doing so?   I was thinking of using something like Norton Ghost to make a copy of the system (It can image a dynamic disk but it can only restore an image to a 'basic' disk) and then restore it to the new array. If something went haywire I could always keep one of the mirrors in a safe place and rebuild the mirror in software.   A few more details: The machine I want to upgrade to RAID 5 is a Power Edge 1750 with (right now) two 37 GB disks in 'normal' mode running Windows Server 2003 SP2. There appear to be two LSI Logic SCSI devices; the first one has the two disks and a 'PE 1x3 backplane' device, and the other has an external Power Vault media changer and tape drive attached. It also appears to have two additional SCSI devices from an Adaptec 39160 card somewhere in there. I suppose I could move the Power Vault to the 39160 card if I had to.

at5147 · Answer

First off, the option to change the channels to RAID mode would be located under 'Integrated devices' in the BIOS. However, you have to have the RAID key in order to do so install on the system board. Without that (and you should have the memory and battery as well) the option will be unavailable.

Second, you will not be able to take the RAID 1 OS based RAID to a hardware based RAID without reinstalling the OS. If you are able to change the channels to RAID, the RAID controller will not pass the drives to the OS until a RAID is setup in the controller and setting up a RAID in the controller on the drives will delete any previously existing data.

And the problem that you may find with using Ghost is the correct storage controller will not be loaded once you switch it to the PERC 4/Di, since that is a different controller all together.

Oh and one more thing, don't change the channel that as your PowerVault on it. It does play well when attached to a RAID controller. You would want to move that to the 39160.

gordonf4df · Answer

> you have to have the RAID key in order to do so install on the system board. Without that (and you should have the memory and battery as well) the option will be unavailable   That's the 'ROMB' add-on I've read about, I believe.  The Power Edge 1750 manual describes how to install it.   > you will not be able to take the RAID 1 OS based RAID to a hardware based RAID without reinstalling the OS   ...that was where I thought Ghost would help, but...   > And the problem that you may find with using Ghost is the correct storage controller will not be loaded once you switch it to the PERC 4/Di, since that is a different controller all together.   INACCESSIBLE_BOOT_DEVICE will happen because the driver for the PERC won't be loaded yet.   Usually when I move a Windows install from one class of machine to another, I attempt to preload the target machine's mass storage driver first.  On IDE/ATA machines I just change the driver to Standard PCI IDE. On SCSI it's more difficult but I usually can install the target machine's card in the source machine, set it up, and then Ghost it. As long as the target machine's driver is loaded and working, it'll boot.   That step would be a little more difficult here considering a PERC 4/Di isn't exactly on its own card.  I have tried preloading drivers directly using Add New Hardware without actually installing the device, but the last time I tried that it was using an Adaptec RAID card that isn't supported anymore. I've yet to try that again with supported hardware.   What if I moved the OS to a disk attached to the Adaptec 39160 first? That driver's already installed and working. Then it'll boot, assuming there's a BIOS on the 39160, and I can add the PERC driver and Ghost it to the new RAID array.   And just to clairify:   > Oh and one more thing, don't change the channel that as your PowerVault on it. It does play well when attached to a RAID controller. You would want to move that to the 39160.   I read that the onboard SCSI does not support using the external port in RAID mode.  I'm assuming you meant, 'it doesn't play well when attached to a RAID controller?' In which case, yes I would want to move the Power Vault to the 39160.

at5147 · Answer

You can try to install to the 39160 or an IDE drive and see if you are successful, but I haven't tried it so I couldn't tell you how it would turn out. Plus you will have to install the OS on the drives with the RAID setup, so I am not sure ho you would get the drivers over to that installation and installed properly. Again, haven't tried so not sure how that would work out.

I recall the channels, with the ROMB installed, either both being, RAID, SCSI or off. I don't think you can mismatch the channel, but I may be thinking of another system. I will have to double check. But if that is the case, then ya you would want to TBU on the 39160.

PowerEdge HDD/SCSI/RAID

Convert Software RAID to RAID 5 on PowerEdge 1750

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