Mirar errores:

smartctl -l error /dev/sda

Hacer test rapido/largo, esperar el tiempo y mirar errores:

smartctl -t short /dev/sda
smartctl -t long /dev/sda

Test Corto:

# smartctl -t short /dev/sda
  

smartctl 5.41 2011-06-09 r3365 [x86_64-linux-2.6.32-26-pve] (local build)
Copyright (C) 2002-11 by Bruce Allen, http://smartmontools.sourceforge.net

=== START OF OFFLINE IMMEDIATE AND SELF-TEST SECTION ===
Sending command: "Execute SMART Short self-test routine immediately in off-line mode".
Drive command "Execute SMART Short self-test routine immediately in off-line mode" successful.
Testing has begun.
Please wait 1 minutes for test to complete.
Test will complete after Mon Jul  7 17:44:35 2014

Use smartctl -X to abort test.

Comprobamos que no ha dado errores:

# smartctl -l error /dev/sda

smartctl 5.41 2011-06-09 r3365 [x86_64-linux-2.6.32-26-pve] (local build)
Copyright (C) 2002-11 by Bruce Allen, http://smartmontools.sourceforge.net

=== START OF READ SMART DATA SECTION ===
SMART Error Log Version: 1
No Errors Logged

El Test Largo indica que tardará unos 130 minutos

# smartctl -t long /dev/sda

Para ver si ha acabado. Vemos que solo ha acabado el corto:

# smartctl -l selftest /dev/sda

smartctl 5.41 2011-06-09 r3365 [x86_64-linux-2.6.32-26-pve] (local build)
Copyright (C) 2002-11 by Bruce Allen, http://smartmontools.sourceforge.net

=== START OF READ SMART DATA SECTION ===
SMART Self-test log structure revision number 1
Num  Test_Description    Status                  Remaining  LifeTime(hours)  LBA_of_first_error
# 1  Short offline       Completed without error       00%       515         -