When setting up a new server it’s very important to ensure that you have proper redundancy in place to protect your data and prevent down time. Lots of client asks me how the new server that they bought will protect their data against hard drive failure. The best redundancy option is to configure you server with the correct RAID configuration before you install your Operating System.
All servers has a built in Array Utility that you need to use to enable your RAID configuration depending on the amount of hard drives you have in the server and what performance and speed you require from the server hard drives.
I will explain the most common different RAID configurations that you will use in your new server:
RAID LEVEL 0:
RAID 0 configuration can be used if you require best performance and speed from your hard drives. I do not provide any redundancy and should not be used on any critical system as any hard drive failure will mean data loss. RAID 0 is not used very often because of the risks involved.
Important features of RAID 0 Configuration
– Minimum 2 disks
– Excellent performance and speed as data blocks are striped
– NO redundancy as the data is not mirrored or no parity available
– ONLY use RAID 0 on a NON-Critical Server
RAID LEVEL 1:
RAID 1 configuration provides excellent redundancy as the data is mirrored between two hard drives. With other words, the one hard drive is always a copy of the other drive and in case of the one drive fails the second drive will take over and all data will be current. This also provides for no down time in the case of hard drive failure.
Important features of RAID 1 Configuration
– Minimum 2 disks
– Good performance
– Excellent redundancy because of the data mirror between the two drives
RAID LEVEL 5:
RAID 5 configuration also provide good redundancy but you need to have a minimum of three hard drives. Data gets striped between two of the drives and the third drive is used for parity. This enables excellent read speed from the hard drives but slower write speed because of the parity that needs to be written.
Important features of RAID 5 Configuration
– Minimum 3 disks
– Good performance because of strip configuration
– Excellent redundancy because of the distributed parity between the hard disks
RAID LEVEL 10:
RAID 10 configuration is probably the best RAID configuration because the drives are striped and mirrored and will provide excellent redundancy and excellent performance. It’s also the most expensive RAID configuration as you require a minimum of 4 drives.
Important features of RAID 10 Configuration
– Minimum 4 disks
– Excellent performance because of striped configuration
– Excellent redundancy because of the mirrored disks
– Best configuration for any Critical Server if you are willing to pay a little extra
This is the most used RAID configurations, but there is some less popular ones too. You can read more about all the other different RAID configurations here.