Hi I know that there is RAID 5, RAID 1 etc, and some RAIDs are better for some types of applicaton behaviour than others. For instance, RAID 1 is supposedly better for transactional logging because of the write behaviour. Does anyone have a list of the different RAID types for Windows servers and which application behavior they suit best? In terms of behaviour, I was thinking; A) Sequential writes B) Sequential reads C) Random writes D) Random reads Also, if parts of the app wanted to carry out a mixure of the above, are we better off seperating them into seperate RAID drives?

With RAID it's always a question of trade-offs and what you choose depends on a number of factors really, not just basic I/O. If you want some off-the-cuff type recommendations, can you please advise: 1) How many physical disks does your server have? 2) What RAID levels does your server / controller support? 3) What is your uptime requirement? 100%, 80%? 4) What is your data loss tolerance? 5) What is your overall goal? Maximize performance, resiliency, or disk space? In general, I find that most people who want a quick solution with a generic type of approach tend to go with RAID 10 where they can, preferentially followed by RAID 5 or RAID 1 depending on how many disks are available. Of course, if you have four disks you might create two RAID 1 volumes so that you have the option of separating application components later on. In sum, it really all depends! If you have an application vendor, I would recommend speaking to them about it as they usually know quite well what is best.

With RAID it's always a question of trade-offs and what you choose depends on a number of factors really, not just basic I/O. If you want some off-the-cuff type recommendations, can you please advise: 1) How many physical disks does your server have? 2) What RAID levels does your server / controller support? 3) What is your uptime requirement? 100%, 80%? 4) What is your data loss tolerance? 5) What is your overall goal? Maximize performance, resiliency, or disk space? In general, I find that most people who want a quick solution with a generic type of approach tend to go with RAID 10 where they can, preferentially followed by RAID 5 or RAID 1 depending on how many disks are available. Of course, if you have four disks you might create two RAID 1 volumes so that you have the option of separating application components later on. In sum, it really all depends! If you have an application vendor, I would recommend speaking to them about it as they usually know quite well what is best.

Does anyone have a list of the different RAID types for Windows servers and which application behavior they suit best? The essential purpose of RAID is to have data redundancy, Nigel already explained about that above. RAID types and application behavior are two different aspects however, they are correlated ! Application behavior do not just depend on RAID type instead several other factors come in picture such as number of drives being used, disk offset which has been used to format the disk, disk read/write speed and how frequently application data is accessed on server etc... Here are some of the links which might help you... RAID Types http://en.wikipedia.org/wiki/RAID Sequential I/O with RAID-5 and RAID-10 http://www.dbforums.com/db2/1664094-sequential-i-o-raid-5-raid-10-a.html Choose a RAID level that works for you http://www.techrepublic.com/blog/datacenter/choose-a-raid-level-that-works-for-you/3237 RAID5 versus RAID10 (or even RAID3 or RAID4) http://www.miracleas.com/BAARF/RAID5_versus_RAID10.txt I do not represent the organisation I work for, all the opinions expressed here are my own. This posting is provided "AS IS" with no warranties or guarantees and confers no rights. - .... .- -. -.- ... --..-- ... .- -. - --- ... ....