[LINK] Leave on, or turn off?

[Adam Todd]

At 05:29 PM 30/11/2006, John Clarke wrote:
>On Thu, Nov 30, 2006 at 04:17:32 +1100, Marghanita da Cruz wrote:
>
> > sometimes it is the redundancy mechanism that is less reliable than the
> > disks themselves...
>
>It is.  Redundancy increases availability but decreases reliability.
>
>Availability is improved because when one disc drive fails your system
>keeps running and you don't have an outage.
>
>Reliability is reduced because you have more things that can break, so
>more things will break.

Yeah, I never understood why people claim that a system with an uptime of 
99% when duplicated means greater than 99% uptime.

Hmmm.

I remember telling telcos that the more hops and links in the chain the 
lower the uptime calculates.