The maximum number of disks that can be used in a RAID 5 configuration depends on the type of RAID controller being used and the capabilities of the controller.
In general, the maximum number of disks that can be used in a RAID 5 configuration is limited by the number of parity blocks that are required to protect the data. In a RAID 5 configuration, one parity block is required for every N-1 data blocks, where N is the number of disks in the array. This means that the maximum number of disks in a RAID 5 configuration is typically limited to around 7-12, depending on the size of the disks and the amount of data that needs to be protected.
However, some RAID controllers support more advanced RAID 5 configurations that use distributed parity, which allows for a larger number of disks in the array. For example, the Intel Matrix RAID controller supports up to 30 disks in a RAID 5 configuration using distributed parity.
It's important to note that the maximum number of disks in a RAID 5 configuration may also be limited by the hardware and software capabilities of the system. For example, some systems may have a limit on the number of disks that can be attached to a single controller or on the amount of memory that is available to support a large RAID 5 configuration.
In general, it is a good idea to use a smaller number of disks in a RAID 5 configuration to reduce the risk of data loss due to disk failure. Using a larger number of disks may increase the capacity of the array, but it also increases the risk of data loss if one of the disks fails.