SU+J Lost files after a power failure

CeDeROM cederom at
Mon Oct 14 17:16:24 UTC 2013

On Mon, Oct 14, 2013 at 7:09 PM, Brad Mettee <bmettee at> wrote:
> On 10/14/2013 12:50 PM, CeDeROM wrote:
>> Then why random files gets damaged as well even they are not
>> accessed/written on power loss? :-)
> Random files can be affected because the sectors of the hard disk containing
> the directory entries for those files, not the file data itself, may be
> damaged (ie: the directory was in the process of being written OR the
> pointer to that SECTOR was in the process of being written).
> It doesn't mean a file was in active use, just that a chunk of the disk with
> data relevant to that file was. Keep in mind, one sector of disk may have
> data for a dozen files in it (or more). Damage doesn't have to occur because
> a given file was in use at the time of a crash.

Isn't there Journal to prevent and reverse such damage?

> If your power grid is prone to failures or blips, I strongly suggest
> investing in a UPS.

I have UPS in my desktop and also I am working on a laptop, so the
power supply is not the only possible cause of system crash.. this may
be faulty driver, hardware failure, kernel panic, etc.


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