Borrowing from
viewtopic.php?p=2739#p2739redwards wrote:Western Digital USB drives hide drive failures and SMART status when hooked up via USB. I have had drives that seemed to work just fine, but when pulled from their cases and attached directly to a computer using SATA, they fail manufacturers SMART testing and such. The drives I were using had 2TB WD Green drives and I even had problems with them after running badblocks on them for weeks.
I would recommend ensuring that your drives get scanned!
… and on the subject of
luck under
is Zevo safe enough? …
Rewind a year or so. Everything that I saw and read (shared experiences) before Lion was released
should have led to trouble-free installations, trouble-free upgrades from Snow Leopard, for the masses. I rarely bother with Apple Support Communities (bugs with the forum
drove me away) but I decided to drop in, for a few days, immediately after Lion was released. Anecdotally, many of the installation-related problems
screamed one thing to me:
silent hard disk failure! … so I left the poor users, wallowing in a mire of "Me
too!" and "I have
exactly the
same problem!", uppercase shouting with five exclamation marks in a row and so on, where in fact, most people's problems were
not the same
I can't estimate what percentage of installations were truly bugged by silent hard disk failures (we'll never know) but …
… the
mismatch – between (a) pre-release test experiences (Developer Preview etc.) and (b) post-release observation of other users' experiences – was great enough for me to think: there must be a better way. So here I am.
Consider: the multiple checksumming routines within a full installation of OS X probably do not extend to checksumming the end results. With so much written and deleted during and after a full installation, it's little surprise: disks that are only
marginally good may be pushed over the edge.
This is not to bash HFS Plus – echoing a sentiment in an Ars Technica review, the file system does what it says on the box. But modern uses of file systems are so much more strenuous, and users' expectations so much higher, that we need approaches (such as ZFS) that can proactively detect problems in good time.
Then for example
Customer Reviews: Western Digital 1TB My Book for Mac - Apple Store (U.S.) paint not a pretty picture – two of five stars based on 168 reviews. Some of the low marks are unjustifiable but overall, it ain't purdy.
Again, I'm reluctant to product-bash. How many of those reviews might be different if the users enjoyed an Apple-integrated method of
properly assessing the state of a hard disk?
ZFS alone is not the panacea – we need complementary approaches to check unused space, and so on. But ZFS should be a huge step away from a past where imperfections remain unknown until it's too late.
badblocksThe observation from redwards is appreciated. I have in Ask Different a question that's unanswered, possibly redundant (I know not enough about CoreStorage):
What free or open source software can I use with Mac hardware to verify integrity of every block of a disk where CoreStorage is used?