Is disk really bad if mkfs.ext4 -c -c reports errors?

Liam Proven lproven at
Wed Jan 11 15:45:22 UTC 2017

On 11 January 2017 at 16:40, compdoc <compdoc at> wrote:
> The only reliable way to tell if a disk is dying is to read its SMART info.

In my fairly extensive experience over the last 20+ years since SMART
has been developed, the reverse is true.

The only reliable sign that a disk has failed is that it has failed.

SMART can say a disk is marginal but then the disk can go on working
for many years. I have had this ,more than once.

SMART can say a disk is 100% perfect and it fails the next day. I have
had this too, many times.

It's _helpful_ and _sometimes_ it gives you fore-warning, but it is
not a guarantee. Disks are cheap, data are expensive. SMART gives you
a warning that a drive _might_ go before it does, giving you time to
replace it. That's worth the cost of a few spares for drives that
don't fail.


Do *not* rely solely on SMART.

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