"I assume this is a RAID 5 configuration, correct?" Strike 1:  Assume.  Never assume anything :)  With 6 physical disks on a PERC 6, you could have a RAID 5, 6, or 10 (6 disks could also be a RAID 0, but given one disk has already failed and the data is still accessible, it could not be at this point).  What you do with the failed disk isn't affected by this fact. 1. The backplane is the board where all the drives connect.  A system with a backplane does not have individual drive cables connecting the drives to the controller - the controller has a cable(s) that goes from the controller card to the backplane, and all the drives connect to power and data through the backplane board.  (SAS does stand for Serial-Attached SCSI, but do not confuse SAS with SCSI - the ONLY similarity is the internal commands supported on the drives - they are not otherwise compatible at all.) 2. DRAC stands for Dell Remote Access Controller.  This allows FULL remote access to the server (console access, so BIOS screens included), plus some other amenities for managing the server remotely.  This has nothing to do with your current problem, so I won't go into more detail (feel free to ask about this).  Mid-life kicker is an update do a device "mid-life" ... so it is a substantial upgrade to the hardware but still carries the name.  The 2950 has three revisions (mid-life kickers) ... I, II, III.  They are all 2950's but have significantly different capabilities (TPM, RAM capacity, FSB, processor support, etc.). 3. TOE stands for TCP Offload Engine ... network performance feature, but again, irrelevant to your current issue. 4. This is just the parts description for your backplane CABLE - it indicates the 6-disk backplane option (there are 4, 6, and 8-disk options).  The backplane was originally manufactured for the PERC 5 - the PERC 6 came out later but is perfectly compatible. 5. Your RAID controller is the PERC 6/i.  The PERC 6 come in two versions:  and Adapter and an Integrated version - the Integrated versions go in systems (like the 2950) that have a dedicated slot that is optimized for that particular controller. Yes, your system has a SAS RAID controller (sometimes the Integrated version is called a "daughtercard").  The ONLY supported cards for the 2950 are SAS controllers ... SAS controllers can take SAS OR SATA drives. It may rebuild automatically, but there is a chance it will not.  If not, then you need to assign the disk as a Hot-Spare to begin the rebuild.  If the drive shows as "foreign", the foreign config must first be cleared before you can assign it as a hot-spare.  This is all done in the CTRL-R BIOS utility for the controller (or from OMSA, which IS an option for ESXi setups as well). Changing the drive is the most basic and simple of all server maintenance.  Whatever you do, do NOT turn off the machine to swap the drive:  If it is hot-swap, swap it hot.
This server houses our small business database, so I don’t want to do anything that might corrupt the data on it.  The other IT staff (a programmer) backs up the files to external hard drives.  I’m new in the IT field, so I could use some advice.  I did not set up the server, and of course the server is a few months out of warranty at this point. The LED display panel on the front of the server shows this error – “E1810 HDD ## Fault”.  I have no way to manage this server, as it was set up as all virtual machines in VMWare ESXi 4.  Right now the programmer doesn’t want to install Dell OpenManage, because the server would first need updated firmware, etc.  When I look at the physical server itself, I can clearly see the hard drive with issues because there are amber lights blinking instead of green.  This is the most detailed information I can get from VMWare console:  Alert! >>Storage  - Drive 5 in enclosure 32 on controller 0 Fw:HS09 – UNCONFIGURED BAD  Warning!  RAID 5 Logical Volume 0 on controller 0, Drives (0e32,1e32,2e32,3e32,4e32,?) DEGRADED Warning! Disk Drive Bay 1 Drive 5: Drive Fault – Assert    Alert! Disk Drive Bay 1 Drive 4: In Critical Array – Assert   Alert! Disk Drive Bay 1 Drive 3: In Critical Array – Assert   Alert! Disk Drive Bay 1 Drive 2: In Critical Array – Assert   Alert! Disk Drive Bay 1 Drive 1: In Critical Array – Assert   Alert! Disk Drive Bay 1 Drive 0: In Critical Array – Assert   Alert!   Since I’m clueless as to what I’m dealing with here, can anyone answer the following questions for me?  I assume this is a RAID 5 configuration, correct?   I obtained this info from the system configuration page on dell.com:                1)Backplane, Dell2950, 3.5X6SAS                                                             2)ControllerDRAC5, PE, Mid-Life Kicker                3)FG0271Card, Backplane, Key, TOE, 2 PORT Enterprise Systems Group                4)MC3601Assembly, Cable SASX4-PERC5X4-X6BKPLN                5)Controller PERC6IINT, Serial Attached ScsiShort Lead  1)      What exactly is a backplane? I could look this up in Wikipedia, but I can probably get a better working explanation from a true network person!  I assume the SAS stands for serial attached SCSI drives, since that’s what the hard drive description is (SCSI). 2)      Is DRAC5 the brand of the controller?  If not, what does DRAC5 mean?   Mid-Life Kicker?? 3)      TOE? 4)      Not sure what this is saying… 5)      What is a PERC6IINT controller, and why does line 4 show PERC5?   I have been reading the Dell troubleshooting documentation and it has some terms I don’t know how to address.  Based on the above information, this server has an SAS RAID controller, correct?  How do I know if I have an SAS RAID controller daughter card (that term is in the troubleshooting steps)?  Finally, we purchased a Dell replacement hard drive.  It’s hot swappable, and we were just going to exchange it with the failed drive.  Will I need to configure anything on the server or drive, or is it as simple as just swapping out the bad drive with the new one?  Will it rebuild without any intervention on my part?  If there seem to be problems, it looks like I will at least be able to monitor something by going into the RAID BIOS, correct?   With my lack of server knowledge & experience, what would you suggest?  Should we just go for it, and try hot swapping the drives after hours?  Or do you think we should “bite the bullet” on this one, and opt for paying Dell a service call to do this?  I may be overly cautious, but I don’t want to be responsible for taking down a critical server when I’m still a new at this.   Any input would be most appreciated!  
Dell Poweredge 2950 HDD Fault; need advice on hot swapping the drive