Re: [smartmontools-support] Frequent file system errors on USB drive

[Volker K. <lis...@pa...>]

On Fri 18 Dec 2015 21:26:21 NZDT +1300, bege wrote:

> I use a Samsung HD400LD USB drive for backups on Windows 7 Professional 
> 64 bit SP1. For some time now while running mirror backups I rather 
> frequently have file system errors on that backup drive. Sometimes they 
> can be repaired using chkdsk, sometimes chkdsk fails and I have to 
> format the drive (did both, fast and full formatting). I am still using 
> the same backup software (Backup4all), also tried another one (Personal 
> Backup), same problem. It seems like the error occurs more on larger 
> backups with very many files. But much larger backups with just one file 
> (zipped system backup, Macrium Reflect) work without any problem. All 
> backups have several GB of size.
> There are no SMART errors, long self test passes without any problems. 
> Memory test also without any errors.
> What may cause this problem?

This sounds like a hardware problem, but could also be a bad USB driver.

To confirm:
The actual hard disk is a spinning platter model (the enclosure model is
of no interest) and you verified that its Reallocated_Sector_Ct,
Current_Pending_Sector, Offline_Uncorrectable are all 0?
And smartctl -tlong passes without problems? If no to any of this,
replace disk. Assuming yes:

Check the hardware data path for errors. I've found USB connectors to be
very hit/miss at times. Replace cables. Use a different enclosure. You
already tried different USB sockets. Connect disk directly to computer -
USB is asking for trouble.

Ensure you have an adequate power supply. If it's a USB-socket-powered
2.5" disk feed it a proper power supply instead. Power dropouts cause
data corruptions you describe.

It's also possible that your USB driver is faulty. A single big file
might work, but many small ones cause non-sequential disk accesses and
the driver (or the enclosure's USB bridge) is getting confused.

Any other hardware fault in your computer would also cause corruption.

Your backup software may at best be a trigger but is unlikely to be a
cause of filesystem corruptions.

My bet would be on the USB system or the enclosure, assuming the disk
itself is OK.

HTH,

Volker

-- 
Volker Kuhlmann
http://volker.top.geek.nz/	Please do not CC list postings to me.