[CentOS] OT - Offline uncorrectable sectors

[Lorenzo Quatrini]

William L. Maltby ha scritto:
> 
> Yep. Only a few copies of the superblock and the i-node tables are
> written by the file system make process. That's why it's important for
> files systems in critical applications to be created with the check
> forced. Folks should also keep in mind that the default check, read
> only, is really not sufficient for critical situations. The full
> write/read check should be forced on *new* partitions/disks.
> 

So again my question is:
can I use dd to "test" the disk? what about

dd if=/dev/sda of=/dev/sda bs=512

Is this safe on a full running system? Has to be done at runlevel 1 or with a
live cd?
I think this is "better" than the manufactureur way, as dd is always present
and works with any brand.

Lorenzo