Replacement of damaged SAS Drive, RAID 5 in Dell PowerEdge R720
I have a Dell PowerEdge R720 with 3 600 GB SAS HD's RAID 5 in a PERC card and this morning I saw the orange alert light and in the display says that "there is an error in DIsk 0, check Drive" (not sure how much time the error is because I rarely enter to the site) so, I have a spare 500 GB SAS drive and I have some questions:
- Since the message in the display says: "check drive" (doesn´t says literally "replace the disk") it means there is something to do in order to fix the disk or it is inevitable to replace it?
- If there's nothing else to do to fix the disk, may I replace the 500GB HD in a 2 HD 600GB array?
- If yes, may I do that with the server running in a Windows session or I have to power off the server?
- If I have to power off the server, do I have to boot with the PERC software and put online the disk and rebuild the array?
- If yes, takes many time to rebuild the array? (I ask this to plan how much time the server will be offline and warn users) the total array space with the 3 600GB HD's was 1TB and there are 450GB used.