Backups was Restoring MBR - Solved

[richb at pioneer.ci.net (Rich Braun)]

"Robert L Krawitz" <rlk at alum.mit.edu> challenged me:
> Think about a financial services company that issues credit cards, and
> they need to store data on every single transaction for years.  They
> *absolutely* need that backup.  Think about however many billions of
> transactions we're talking about every month.

OK do some math.  How much data per transaction?  Let's call it 2 Kb, probably
less (a hundred bytes is enough for the name, card number and other minimal
stuff).  A gigabyte can hold 500,000 such transactions.

If you're doing the backups for the Wal-Mart store chain then I agree with
you.  But most of us work for a non-retail establishment that doesn't issue
credit cards.  In fact I'd hazard a guess that there are only a couple hundred
companies in the entire world that have to handle more than a million
transactions per day.

So if we assume a typical company that does 100,000 or fewer transactions per
day, then a month's worth of data would take about 6 gigabytes.  *Not*
terabytes.  And you only need to keep a few months of data online, older data
can be put in an archive that doesn't need daily backup.

Does your office do 100,000 transactions per day?  I'm still trying to come up
with a reason for *terabytes* of online storage.

> You'd be surprised (or maybe not, if you reflect on it) ...

Are you surprised at my analysis?  I have reflected on this and am simply
amazed at how much data companies are storing.  It just can't be useful.

-rich