Recently got a dell T320 with a percH310 controller, and I've decided to put the OS on a raid 5 of 3x300GB 15k SAS drives but would like a hot spare, we have a spare 15k 300GB sas drive which has been a hot spare in the old server, and has never been used it's from 2013. My priority here is placed on redundancy and reliability/uptime over performance.
1) Will this have any detrimental/negative effects such as reduce reliability of automatic raid rebuilds, load other disks higher when in use, or any such?
2) Would i be better off setting all 4 up in a raid 10 array or again could this older drive cause me any potentially dangerous circumstances or even just reduce performance of the other drives?
This won't be containing most of the data this will be on a separate SATA raid 10 of 6TB drives.