Thursday 10 April 2008

Conquest Server and 2.8TB RAID - The Battle!

Its been some time and we have had many hiccups with our new Conquest Dicom server.
First of all we battled to get 4 x 1TB drives as they seemed to be rare in our part of the world.
We then had some issues as one of the disks failed due to the case being too cramped and hot, so we got a bigger more spacious and cooler case to house the hard drives.
Then we had a problem with Windows Vista not picking up the entire RAID array. It seems as though Windows Vista Business Edition 32bit can only install itself on a partition that is more than 3TB. So then we installed a smaller 160GB disk to run the operating system.
The next problem is that Windows Vista can now recognise the whole RAID array, but it automatically partitions it into a 2TB partition and a 700GB partition. You cannot make the whole disk one partition!
So my current plan now is to retain my old conquest server that is running out of space, install Ubuntu Linux on the 2.8TB drive machine and share the disk. Then mount the disk as a network drive on the original conquest Dicom server and see if that allows us to have the full 2.8TB drive space available for Dicom images.

Some of the other things I thought of doing where the following:
  • Setting up multiple smaller conquest servers for each modality.
  • Setting up multiple instances of conquest server on a single machine and depending on the AE Title sending the data to different partitions on the disk.
  • Using Windows Vista Business Edition 64bit
These options although viable did not seem practical for our usage.

The major benefit of this setup is that we are utilising an Open Source OS and therefore we can save some money instead of forking out for Windows. I also think that by using a network share as the primary storage for the Conquest Dicom server we will be able to more easily swap out storage servers in the future by merely adding a new mapping to another server, etc.

Lets hope that Ubuntu does the trick! I am installing it as we speak. (Hold thumbs that the RAID configuration works!)
PS: Raid Calculatator: http://www.ibeast.com/content/tools/RaidCalc/RaidCalc.asp
4 x 931GB HDD in RAID 5 Array = 2.793TB