A customer wants to build an "all-in-one" CMS server, i.e. one machine that will run:
- RDMBS
- App server
- web server
- File storage
The CMS is expected to be used for a lot of large files, but will not have a large amount of concurrent users (10 requests per second at most). High availability is not a major concern.
So what would be the best RAID config to support this? I'm thinking that RAID 0 would be best to deal with the large files, probably RAID 1+0 to reduce the chance of outages. Is RAID 5 a viable option? Or perhaps forego RAID completely?
Never put a production machine into the wild without disk level redundancy! Even if "high availability" is not a concern. YMMV.
I'd buy a 6Gbps SAS-based dual-PSU DAS box with lots of 300GB 2.5" 15krpm disks and a quality matching hardware-RAID-10 capable disk controller.
Something like a HP MSA 70 and P800 controller - or similar.
If you can, I'd configure two separate logical volumes... one RAID10 and one RAID5 or RAID6. Use the RAID10 for any database/app stuff, then the RAID5 or RAID6 for file storage. The key point to performance will be setting your stripe size, which should be configured based on the size of data you plan to store on it. Too much info on that to go into detail here, so Google is your friend. :)
Unless you want to become a hardware expert, I'd first of all suggest software RAID. It's much easier to set up and manage than hardware RAID, and for a medium-traffic site like you describe it certainly performs just as well.
The appropriate RAID level depends on your data volume. If you can afford it and the data fits, you can't do much wrong with RAID 10. If you need to go higher volume, then RAID 5 is the next best option, although you will sacrifice some write speed, especially for your database. If you're concerned about that, it'd be best to try it out with your hardware and software.