Configure with Single Raid 5, or multiple Raid 1 / Raid 5?? 1

[pepper08]

Hello everyone,

I am brand new to server configuration, and especially brand new to Raid setup and configuration. I have done some reading on my own, but wanted to ask for some recommendations.

I am going to be setting up a previously-owned Win2000 SMB server that one of our customers just purchased. The server came in this week and I had a chance to physically review the hardware.

The server is a Compaq Proliant ML350 with a SmartArray 641 controller, and a 5 disk array (5 18GB drives).

This server will be the first and only server for the company (for at least a year) and will act as a network file server (along with being the DC, DNS, and WINS server). There are 10 users who will be accessing the server.

The previous company that owned the server wiped it clean, and setup the drives into a single Raid 5 configuration with a single 50GB "C" drive (4 drives in the Raid 5 config with the 5th drive acting as a spare).

My questions are:

1) Would it be better to redo the array configuration and set up a 5-10GB Raid 1 configuration (across 2 of the disks) for the "C" drive, which would then only contain operating system files....and then configure the remaining freespace into additional Raid 1 and/or Raid 5 configurations for data files (creating a "D" drive, and others as needed)??

2) The controller card for the array has 2 ports on it, but currently there is only 1 port in use (there is only one cable connected from the controller card to the disk array). If I reconfigure the array into multiple Raid 1 / Raid 5 configurations, will I see any benefit with only 1 contoller? Can I add another controller to the array?

3) With the server configured as it currently is (single Raid 5 config), why am I missing 20gb of space? (4 drives x 18gb each = 72, but bios and operating system only reports ~50gb). Is the missing space just part of the overhead with Raid 5?

TIA,

Dave

 

[spi200]

Hi Pepper

YOU lose the disk space on RAID 5 because one drive is taken for the parity. In a raid 5 you can lose one drive (any drive) and because the parity is striped across all the drives in the raid set it can rebuild it self.
Here is my 2 cents worth, you have two options as you mentioned.
1. Make one RAID 5 set (forget the hot spare) for about 50GB. This is safe and secure for a small company and I have plenty of Servers in production where I work similar to this. Down side is RAID 5 is a little slow on Writes (Reads are fine) so you may not see the best performance.
2. Make a RAID 1 mirror with 2*18 Gb drives for a total storage of 18 Gb which you can divide up into your C: drive and you swap drive. The remain 3 drives become your RAID 5 for a total of approx 36 Gb ( hot spare not an option as RAID 5 needs 3 drives as minimum) - total disk space is about hte same, but the Server performance will be slightly better as the swap (Lots of READS\Writes) will be on a fast RAID 1 mirror ( sometimes refer to as RAID 1+0 or just a hardware mirror) and this disk activity will be separte from your RAID 5 set where your data is located. Again both options are safe, its just up to you which way you want to go.
Good luck

David