We have a Dell PowerEdge T410 server running CentOS, with a RAID-5 array containing 5 Seagate Barracuda 3 TB SATA disks. Yesterday the system crashed (I don't know how exactly and I don't have any logs).
Upon booting up into the RAID controller BIOS, I saw that out of the 5 disks, disk 1 was labeled as "missing," and disk 3 was labeled as "degraded." I forced disk 3 back up, and replaced disk 1 with a new hard drive (of the same size). The BIOS detected this and began rebuilding disk 1 - however it got stuck at %1. The spinning progress indicator did not budge all night; totally frozen.
What are my options here? Is there any way to attempt rebuilding, besides using some professional data recovery service? How could two hard drives fail simultaneously like that? Seems overly coincidental. Is it possible that disk 1 failed, and as a result disk 3 "went out of sync?" If so, is there any utility I can use to get it back "in sync?"