Interesting statement. You're arguing the reliability of these modern
giant driver, yet use RAID 10 instead of simple spanning or striping. I
Failure during backup is of less concern. Failure of the source
media/system during _restore_ is. Read this thread and the previous
thread from Eli a few months prior. It will open your eyes to the peril
of using a D2D backup system with 2TB WD Green drives. His choice of
such, along with other poor choices based on acquisition cost, almost
cost him his job. Everything is cheap until it costs you dearly.
http://comments.gmane.org/gmane.comp.file-systems.xfs.general/35555
Too many (especially younger) IT people _only_ consider up front
acquisition cost of systems and not long term support of such systems.
Total system cost _must_ include a reliable DRS (Disaster Recover
System). If you can't afford the DRS to go with a new system, then you
can't afford that system, and must downsize it or reduce its costs in
some way to allow inclusion of DRS.
There is no free lunch. Eli nearly lost his job over poor acquisition
and architecture choices. In that thread he makes the same excuses you
do regarding his total storage size needs and his "budget for backup".
There is no such thing as "budget for backup". DRS _must_ be included
in all acquisition costs. If not, someone will pay dear consequences at
some point in time if the lost data has real value. In Eli's case the
lost data was Ph.D. student research data. If one student lost all his
data, he may likely have to redo an entire year of school. Who pays for
that? Who pays for his year of lost earnings sine he can't (re)enter
the workforce at Ph.D. pay scale? This snafu may cost a single Ph.D.
student, the university, or both, $200K or more depending on career field.
Really? Eli had those WD20EARS online in his D2D backup system for less
than 5 months. LTO tape reliability is less than 5 months? Show data
to back that argument up please.
Tape isn't perfect either, ...
