Estimating RAID 1 MTBF?

wrote in
news:1090041101.742428@smirk:

[snip]
This is where you get
yourself a big HP server, run IBM DB2 on it, and put the data on four
Hitachi Lightnings (two of them at the local site, each internally
RAIDed, mirrored across the two with a LVM or a SAN virtualization
box, and each then synchronously remote mirrored via rented dark fiber
to two offsite facilities).

Does it have to be rented? Some of us just plow it down ourselves

Ah, the wonders of being a telco.

By the way, all brand names in the
preceding sentence are meant as humorous illustrations; the fact that
they might be my former, current or future employers is one of these
funny coincidences. This system will cost you several ten M$, but it
is unlikely to go down or lose data.

Or you could get fairly decent hosts, running oracle RAC or other sorts of
clusters off mirrored HDS9570's or Clariions and have an uptime that's just
a fraction lower than running on big iron (or even higher, if you're lucky
enough to get a (as said by a Sun techie) "Monday model" E10k.)

If it happens to lose data (for
example because the field service and support team of the vendor who
put it together and manages for you f***ed up, which does happen in
real life), the CEO of the vendor will call your CIO, and offer to
kiss any bodypart the CIO wants to have kissed ... not to mention some
major financial apologies. In this environment, quietly marking a
sector bad would be tantamount to treason, and might even start a
lawsuit.

Hmm, we got an "Oops, sorry" when a midrange storage system by one of the
three-letter-guys experienced a double disk fault in a RAID 5.

[snip]
I've been
thinking of getting a cheapo IDE RAID card (I could probably swipe a
used 3Ware 4-port card from the office, we used a few of them in a
test setup and they are now gathering dust)
[snip]

Send me one


--
/Jesper Monsted