[CentOS] lvm 1 drive fails whole vol data lost

Sat Dec 25 13:47:16 UTC 2010
Ryan Wagoner <rswagoner at gmail.com>

On Sat, Dec 25, 2010 at 2:15 AM, Benjamin Smith
<lists at benjamindsmith.com> wrote:
> IMHO, very few people really need RAID. In many (most?) cases, the added
> complexity of RAID is as likely to cause an increase of failure rate similar
> to or greater than the reduction of failure rate caused by the resiliancy of
> hardware. RAID won't protect you if you issue a perfectly legitimate command
> to delete data that was made in error. I once thought I needed RAID, and since
> realized the error in my ways, finding that the cases where RAID helped (one!)
> was vastly outnumbered by the cases where it made no difference (10? 11?) or
> actually worked against me. (2) Now, I don't bother with RAID even though my
> needs have grown from one server to 16, instead providing redundancy at the
> machine level: if a server goes, another picks up the load, in most cases
> automatically, in near-real-time. I can do this because I host a custom-made
> application with these objectives carefully designed for.

I'm not sure why you have so many problems with RAID. I will never run
a production server without RAID. A simple mirror (RAID 1) potentially
increases up time and doesn't add much complexity. It allows you to
replace a failed drive without reinstalling the system or bringing it
down. Sure you could restore from backup, but that takes additional
time. Failing over to another server is always great, but why be one
server down for a simple drive failure.

Not to mention the speed increases from RAID 5 or 10. For busy file
servers and database servers you need more throughput than a single
drive can provide. With the speed of processors these days the system
will be greatly underutilized in most cases with a single drive.

Ryan