NL CPG, RAID 6?

[Joseph]

Guys, does anyone advise reasoning behind this best practice?

Best practice: NL CPGs should be of the RAID 6 type by default.
The “set size” (data to parity ratio) can be changed from the default value of 8 (6+2) if the system configuration supports it. RAID 5 is not recommended with NL disks.

[Schmoog]

Rebuild time with the nl drives is very long. Think hours at best, days in some cases, so you want the additional protection in case of multiple failures in a short period of time

[afidel]

BER is also several orders of magnitude worse on NL so you have to worry about URE during rebuild.

[Joseph]

Thanks for clarification guys!