Hot swapping hard disks, RAID 5 with hot spare

Config

System

RAID 10

RAID 10 (or 1+0), includes nested RAID levels 1 and 0, or a stripe (RAID 0) of mirrors (RAID 1). The total disk space available is the total number of disks in the array (a minimum of 4) divided by 2. Any drive from a RAID 1 array can fail without loss of data. However, should the other drive in the RAID 1 array fail, all data will be lost. In this situation, it is important to replace a failed drive as quickly as possible.

Note: Fortinet recommends using RAID 10 for redundancy instead of RAID 5 on FortiAnalyzer units with software RAID. RAID 5 causes system performance issues.

RAID 50

RAID 50 (or 5+0) includes nested RAID levels 5 and 0, or a stripe (RAID 0) and stripe with parity (RAID 5). RAID 50 provides increased performance and also ensures no data loss for the same reasons as RAID 5. For the following FortiAnalyzer units, data is recoverable when:

•up to three disks fail (FortiAnalyzer-4000/4000A)

•up to two disks fail (FortiAnalyzer-2000/2000A).

RAID 5 with hot spare

FortiAnalyzer-2000/2000A and FortiAnalyzer-4000/4000A units can use one of their hard disks as a hot spare (a stand-by disk for the RAID), should any of the other RAID hard disks fail. If a hard disk fails, within a minute of the failure, the FortiAnalyzer unit begins to automatically substitute the hot spare for the failed drive, integrating it into the RAID array, and rebuilding the RAID’s data.

When you replace the failed hard disk, the FortiAnalyzer unit uses the new hard disk as the new hot spare.

Note: RAID 10 requires an even number of disks. For example, on the FortiAnalyzer-2000/2000A, when selecting RAID 10 with hot spare, the FortiAnalyzer unit will use four of the six disks in the RAID 10 array, keeping one as a hot spare. The additional hard disk will be defined as idle.

The FortiAnalyzer-2000/2000A and FortiAnalyzer-4000/4000A also supports hot swapping of hard drive disks during operation. For more information, see “Hot swapping the FortiAnalyzer-2000/2000A and FortiAnalyzer-4000/4000A” on page 66.