Table of Contents - 

Document Change History - 

Document Scope & Audience -

Document Scope

SMART tests are rather involved and are rather overwhelming before you know where to look. The idea of this article is to shine some light on SMART tests, when to schedule them and what to watch out for.

Document Audience

Targeted Audience List (If Any)

List any specific targeted audience here with an at symbol (@) in the Target column with the targets name. Notes field should be used to denote WHY the person is being targeted in the document to get notifications, etc.

SMART Summary -

Self-Monitoring, Analysis and Reporting Technology

This monitoring system is included with disk drives (traditional HDDs, SSDs, and eMMC) and its goal is to proactively monitor drives to hopefully catch potential failing drives before they actually fail. This is done by reporting on a vast array of indicators and attributes that can be quite overwhelming. Unfortunately, this is compounded by the fact these indicators and attributes are not standardized across the industry and those that appear to be the same across vendors are often interpreted differently. 

We hope to bring some clarity to this subject so that this monitoring system can become of greater value to our users and hopefully prevent data loss. 

Manually Running Tests

Installation

Ensure that smartmontools is installed, if not, please install according to the OS you are using either apt-get or yum

# yum install smartmontools

# sudo apt-get install smartmontools

Confirm SMART is supported

# sudo smartctl -i /dev/<device>

Executing Tests - 

# smartctl -t short /dev/<device>
# smartctl -t long /dev/<device>
# smartctl -t conveyance /dev/<device>

Specific time frames can be gathered by executing the following command.
# sudo smartctl -c /dev/<device>

Testing Schedule - 

The following tests are a good foundation to start with. I would suggest that the frequency of the tests not be adjusted, but the time in which these tests occur can be shifted to meet the needs of the system and environment. These should also occur during non-peak times. For example I typically schedule them in the middle of the night short tests at midnight on Fridays and long tests at 8pm Sundays. 

Anything more can shorten life of the disk but ultimately is moreso a waste of time.

Scheduling Tests - 

Testing can be scheduled and automated to avoid having to remember running tests manually on a regular basis. This can be done several ways, however, using smartd.conf is discussed below.

/dev/<device> -a -m user@domain.com -o -s (S/../../1/5|L/../../6/1)

The example above will run on the specified device, monitoring all SMART features, seding a report to user@domain.com after the Short tests completes which is scheduled to run on the 1st day of the week at 5AM while the long test is scheduled for the 6th day of the week at 1AM.

Options and more explanations below.

What Metrics Matter - 

When a Disk is Suspected Bad -

Confirm the device in question and run a long test so that the entire disk is scanned and tested. As stated earlier this can take several hours to complete but will provide a comprehensive overview of the disk's health.

The SMART log (smartctl -x /dev/<device>) can then be attached to a ticket with Exxact to validate RMA replacement if within the 3 year warranty we provide. If the system is older than that, most drive manufacturers offer a 5 year warranty and they can be contacted directly.