Re: SSDs - RAID or Mirror ?

"James H. H. Lampert" <jamesl@xxxxxxxxxxxxxxxxx> wrote on Mon,
20 Oct 2014 15:29:30 GMT:

is the most extravagant form of RAID, such that
failure of the whole array requires not only the failure of at
least two drives, but of two drives in the same mirrored pair

Mirroring protects from more than disk drive failures.

I have customers running with multiple CEC POWER6 boxes who have
processor node level mirroring. Meaning they can lose a whole
processor enclosure and continue to operate. Before getting
paired or high availability RAID adapters this was not possible
.... for any operating system.

RAID 10 with the EJ0L adapters properly placed in I/O enclosures
can create similar level or redundancy except when an adapter
fails, write cache will be disabled and performance will suffer.
A properly validated mirrored config can even keep the write
cache operational with an adapter failure in some situations.