We are planning to expand our existing SAN. Is there any calculator available that can tell us how many disks are required for the amount of usable space or, vice versa, how much space we will get from x number of disks? Thanks in advance.
Thank you for the question. Expanding your SAN sounds like a great idea, and I believe that you are talking about expanding the space in your SAN environment by adding disk space to your current disk array, correct? If so, you need to determine the disk layout and the vendor requirements for space for the specific configuration that you require. All disk array vendors have their own calculators, which you can use to determine the actual useable space for a specific configuration on a specific array.
To determine generic RAID configuration and space utilization, I have been using a Web-based tool from iBeast.com for some time.