Redundancy - RAID 1 or Server Mirroring
Server Mirroring :-
When you are connecting two servers together you are performing what is called Server Mirroring. A mirrored servers architecture has two servers that are identical in data and configuration. First server is the master server and other is slave server. Typically in a mirrored servers architecture, if one server goes down the other takes its place which ensure that there is 100 % uptime for sites hosted as they start to resolve from the slave server in the same manner as they used to on the master server.
RAID 1 :-
RAID 1 is just mirrored drives which means identical data on two drives of the same server so that data is not lost so long as one disk survives. Total capacity of the array is just the capacity of a single disk. The failure of one drive, in the event of a hardware or software malfunction, does not increase the chance of a failure or decrease the reliability of the remaining drives
Server Mirroring is more expensive as compared to RAID 1 as it involves two physical servers to be mirrored while RAID 1 involves two or more disks on the same server.
RAID provides Hard disk redundancy while server mirroring provides system redundancy.
