[CentOS] raid 5 install

[John Hodrien]

On Mon, 1 Jul 2019, Warren Young wrote:

> If you then bring up battery backups, now you’re adding cost to the system.  And then some ~3-5 years later, downtime to swap the battery, and more downtime.  And all of that just to work around the RAID write hole.

Although batteries have disappeared in favour of NV storage + capacitors, meaning you don't have to replace anything on those models.

jh