When you have multiple arrays configured in the MD3000i as long as the hot spare is configured as a global hot spare, and it is larger enough that is can be used in either array, then when a drive fails that hot spare will rebuild in its place. Below is the link for the user guide. If you go to page 33 it talks about the hot spares and explains the global hot spare process. support.dell.com/.../HOMA00MR.pdf Let us know how it goes.
Hi, I currently have 6xNearline SAS 750GB drives in my MD3000i. I need more performance so i will be adding 2xRAID 1 arrays running on 15K SAS disks. These will be seperate RAID arrays obviously, so my question is do I need 2xHot Spares or can 1 physical disk be a hot spare for the two arrays? Thanks  Andrew.
MD3000i Hot spare