Hard Drive, SSD, and System Testing with Scannerz
and Scannerz Lite for Mac OS X

Overview
 
This introductory document is intended to illustrate how to perform basic tests on hard drives, SSDs, and systems using both Scannerz and Scannerz Lite. FSE and FSE-Lite, Phoenix, and Perfomance Probe 2, which are included in the Scannerz package will not be addressed. This page covers only the basics of using Scannerz and Scannerz Lite. The user manuals provided with both products contain many more details.

What are Scannerz and Scannerz Lite?
 
Scannerz and Scannerz Lite are both hard drive, SSD, and system test tools developed for Macs using Mac OS X versions 10.5 (Leopard) through 10.11 (El Capitan) with Intel or PowerPC processors. We provide updates for new OS versions usually within a week or two after the release of any new operating systems free of charge.
 
Scannerz is the fully featured version of the product and is intended to be used to by people that not only want to test their systems, but if problems are encountered, be able to determine the causes and possibly repair or remedy the problems themselves. Scannerz Lite  is intended to be used by people that want to identify if their systems have problems, and if present, take it into a qualified repair center for further evaluation.

Scannerz has three test modes known as Normal Mode, Diagnostics Mode, and Cursory Mode, whereas Scannerz Lite has only one mode which is essentially the equivalent of Scannerz' Normal Mode.

Scannerz can be used in a Normal Mode test for evaluating drives and systems to ensure that they're working properly. If problems are encountered, troubleshooting may be performed by using Scannerz in its Diagnostics Mode. Diagnostics Mode tests are, for the most part, automatic. Additionally, a user can configure custom tests using Scannerz Cursory Mode. With Scannerz the user will be able to do the following:
 

• Perform standard surface scan tests on a hard drive or SSD to detect bad and weak sectors or blocks
• Perform seek scan tests on a drive
• Detect data corruption occurring between the drive and the system
• Detect memory problems.
• Detect logic board problems or other problems that yield intermittent or heat related malfunctions or delays.
  
• Detect and identify abnormally long operations such as head parking events and system or drive timeouts
• Help isolate possible cable and connector problems
• Analyze the historical performance of a drive over time
• Use Cursory Mode to analyze problems in more detail and isolate the source of problems
• Monitor the drive for S.M.A.R.T. failures during surface scan tests
• Perform drive probing on a drive with confirmed bad sectors to evaluate how extensive the damage is
• Using FSE or FSE-Lite, identify applications generating excessive drive activity
• Using Phoenix, create an emergency boot volume and perform basic volume cloning
• Help isolate other performance problems with Performance Probe 2

 

Scannerz Lite is intended to be used by people that aren't interested in evaluating problems, but rather want a low cost way to perform a test and if there are problems, take it in for servicing without pursuing the issue any further. With Scannerz Lite, the user will be able to do the following:
 

• Perform standard surface scan tests on a hard drive or SSD
• Perform seek scan tests on a drive
• Monitor the drive for S.M.A.R.T. failures during surface scan tests on internal drives
• Perform drive probing on a drive with confirmed bad sectors to evaluate how extensive the damage is
• Detect the presence of abnormal system problems.
  

 
Both Scannerz and Scannerz Lite are based on a technology known as fault detection. Many logic board or even software related problems may exhibit the same symptoms to an end user as those typically associated with problematic hard drives or SSDs. When Scannerz or Scannerz Lite are performing a Normal Mode test (the only mode available for Scannerz Lite) they are not only looking for media problems (problems with sectors on a hard drive or memory blocks on an SSD), they are also monitoring the system looking for abnormal timing deviations. Such deviations, which we call timing irregularities, or irregularities for short,  can often be sourced to another problem, such as a faulty cable connected to the drive or even a logic board problem.

Most other test tools available for Macs will perform a test on a drive and look only for I/O errors, but both Scannerz and Scannerz Lite will be able to detect not only I/O errors often associated with a bad sector on a hard drive or SSD, but also some of the timing problems described above. If Scannerz finds significant I/O errors and/or timing irregularities during a test, the user may put Scannerz into Diagnostics Mode to evaluate the problem and help isolate it. If Scannerz Lite detects such problems, the user should consider the unit being tested as having problems and take the unit in for servicing (once again, Scannerz Lite is designed to simply tell a user if they have problems, whereas Scannerz can help the user find the source of the problems).

 

 

The Basic User Interfaces for Scannerz and Scannerz Lite
 
The basic user interface for  Scannerz and Scannerz Lite are as follows, however there is no tabbed selector in Scannerz Lite allowing the other test modes:

When Scannerz or Scannerz Lite first start up the window will appear similar to that shown above. The elements of the basic user interface are as follows:

Drive/Volume Selection:  Primary drives and their volumes are shown in this section. The drive/volume listing is scrollable and the user scrolls the window (if needed) to find the desired unit to test and simply clicks on it to select it.

Selected Drive/Volume Info: After a unit is selected as described above, this section fills out with information about the selected drive or volume. This will also report on the S.M.A.R.T. status of the drive. During all media scan tests, S.M.A.R.T. status is periodically checked in case a drive is failing.

Drive Display Mode: This allows the drives and volumes to be organized in different ways to make it easier to identify the drive configurations, particularly those associated with more complicated configurations such as Core Storage and RAID components.

Test Mode Selection: This is not present on Scannerz Lite, only Scannerz. By clicking on one of the tabs using Scannerz, you can easily switch between its three modes of operation: Normal Mode, Diagnostics Mode, or Cursory Mode. Scannerz Lite essentially functions in the equivalent of Normal Mode for Scannerz.

Test Progress and Results: This area identifies the overall progress of the tests and identifies any problems detected. In the test data shown above no errors or irregularities have been detected during either the media (surface) scan or the seek scan.

Testing Controls: Tests may be controlled using the buttons identified above. Unlike other testing tools, with Scannerz and Scannerz Lite you may stop a test, save the data, and resume the test at a later time or even day. This is particularly useful for very large drives or to stop a test and examine any detected problems using Diagnostics Mode (not available on Scannerz Lite).

 
 
What Are the Signs of a Drive or System Problem?
 
The typical signs of drive or system related problems are characterized by some the following:
 

1. Unexplained lock ups or delays, often accompanied by "spinning beach balls" when using the system
2. Copies stop midstream for no apparent reason
3. Dialogs appear indicating the operation couldn't be completed which may be accompanied by an I/O error warning
4. Problems booting the system
5. Certain applications become dysfunctional when specific tasks are started
6. A question mark appears when turning the system on and system fails to boot.
7. A prohibited sign appears when turning the system on.
8. Repetitive noises come from the drive when attempting to access certain files.
9. Abnormally loud drive noises, such as clicking, grinding, or squealing noises.

 
 
This list is not complete, it's simply a list of the most likely problems that can be related to a drive or system. More information on hard drive problems may be obtained by visiting our How-to section of this web site and review the section on problems with hard drives and SSDs.
 
In the following two sections we'll describe how to perform basic tests using Scannerz, followed by Scannerz Lite. Keep in mind this is an introductory document and details about Scannerz Diagnostics Mode will only be covered briefly.


Performing a Basic Drive Test Using Scannerz
 
When using Scannerz, typically you run a full test on a volume or drive in Normal Mode, and if needed, run a Diagnostics Mode test. If Scannerz detects problems the user may stop the Normal Mode test and go right into Diagnostics Mode if they like. Cursory Mode is primarily used for individuals that wish to design and perform custom tests on a device.
 
A Normal Mode test can be started, paused, stopped, and resumed. For example, if you have a large drive (such as a 2TB backup drive) that you want to test, running a test non-stop may take a very long time. With Scannerz, you can stop a Normal Mode test, exit the application, and then resume the scan where it left off at a later time.

A Normal Mode test is complete when the entire media has been subjected to both a surface and seek scan.  The time it takes a  Normal Mode surface scan to complete is dependent on the size of the volume or drive, the data transfer speeds from the media and it's controller,  and finally the speed of the interface itself. The larger the size of the drive or volume, the longer a Normal Mode surface scan will take to complete. A seek scan test on an electromechanical drive will test it for possible malfunctions or deterioration of the positioning mechanisms in the drive, whereas on an SSD it will be monitoring how evenly block access is distributed across the drive. During all Normal Mode tests Scannerz will also be monitoring the system to see if any timing deviations are being detected.
 
Step by step instructions for performing a Normal Mode test are as follows:
 

1. Stop all other applications running on the system. This is more or less required on older, single core systems, but is recommended for all systems.
   
2. Navigate to the Applications → SCSC folder
3. Double click on the Scannerz application icon. You will need to enter an administrative user ID and password before Scannerz will start to launch as shown in the screenshot below.

4. Wait for Scannerz to load all the system and drive information. If some drives are asleep it may take a bit longer for Scannerz to start because it won't register the drives until they wake up. As the system and drive information is loaded, drop down windows will indicate whats going on and when complete, close. This is illustrated in the screenshot below.

5. After system and drive information is loaded, click on the “Scannerz” menu item, and then select “Preferences” from the pull down and verify that the preferences are set properly (preferences are described in the users manual.)  This is illustrated in the screenshot below. Once you're familiar with Scannerz, you probably won't need to do this often, but it can't hurt to check!

6. Along the top tabbed panel of the bottom half of the user interface, click on the “Normal Scan” tab to put the application into Normal Mode. The screenshot below illustrates an internal  drive named "Snow Leopard H" selected for testing. "Snow Leopard H" is indented with respect to it's primary drive, labeled "Primary Drive: disk0." Scannerz uses different icons to represent the type of interfaces which are described in the manual. Other volumes showing on this drive are "Lion H,"  "Mountain Lion H," and "Mavericks." If the user scrolled a little further down the recovery partition would be displayed as well.

7. If you're using a more complex drive configuration such as Core Storage or exposeable RAID, you may wish to select the CS/RAID button in the "Selected Drive or Volume" section to make it easier to identify the components. In the image below, the "CS/RAID" option has been selected, which will filter out and show only the visible components that use Core Storage, RAID, or both. In the screen shot below there is a Fusion drive comprised of a USB and Firewire drive making up the logical volume named "ElCapitan" and a RAID volume named "StripedUnit2" is showing it's first member. If the window in the drive list was scrolled it would expose all the RAID members.

8. If you wish to monitor the logging activity with the logging window, from the Scannerz menu bar, select “Window” and then when the pull down menu comes down, click on “Logger Display”. This step is optional and the logging window may be opened and closed any time during a test. Logging information for a surface scan is updated at roughly 1GB intervals and is fairly slow, and seek scan information is updated at the end of each seek scan increment which happens quickly. The logging window is most useful in Diagnostics Mode.
 
9. Click on the “Start Scan” button. A series of dialogs will appear in sequence that will allow you to configure the name of the log file and its location if you wish to change the name/location, and if the test is one that's being resumed one will appear allowing you to resume the test. Dialogs of this nature are self explanatory and described in detail in the user's manual.
 
10. After responding to the dialogs, the tests will begin or resume, depending on whether or not this is a new test or one that's being continued from a previous session. The following screenshot shows Scannerz performing a surface scan on volume named "Snow Leopard H" The blocks (SSDs) or sectors (hard drives) being scanned are described in the text to the right of the field labeled "Current Test Underway," and the progress bar changes as the scan progress advances.
 
When a hard drive, SSD, or system is working properly (unless it's a very slow hard drive) the text field associated with the test underway will likely change so rapidly the user won't be able to read it. However, when Scannerz hits a bad or weak region, or it encounters some type of problem, it will almost come to a stop, perform a cursory analysis on the region, and then flag it for evaluation for Diagnostics Mode. It will also increment the counts associated with a surface scan error or irregularity, as described in the manual. Re-evaluating such problems in Diagnostics Mode is more or less critical in such cases because a system can generate I/O errors that may be caused by another system problem, rather than the hard drive or SSD itself. The purpose of Scannerz is to help you properly get to real the root of the problem!

11. During testing, a user may pause a scan by selecting the “Pause Scan” button and resume it by clicking on the “Start Scan” button, or terminate it using the “Stop Scan” button. A Scannerz Normal Mode test may be stopped completely, allowing the user to terminate the test (and Scannerz if desired) and then resume the test at a later time or day. This is convenient if the drive is large and the test will take a long time to complete.

Important note: If Scannerz detects errors or irregularities before a Normal Mode scan completes, it is not necessary to scan the entire drive or system. This is already indicating the presence of problems, and you may wish to stop the test immediately, save the test results, and go right into Diagnostics Mode for evaluation.

The two screenshots below show the dialogs that Scannerz will present to a user allowing them to stop a scan followed by the option to resume a scan. The dialog associated with resuming a scan will be presented to the user during the sequence that begins after the "Start" button has been selected. Further details are provided in the users manual.

12. When a Normal Mode test completes successfully, a dialog asking whether or not you wish to review the summary report will appear. This report is in rich text (rtf) format and will be opened in TextEdit.app if you wish to view it. Selecting the option to review the file will allow you to save the file under another name and folder if you wish to do so. A screenshot of the summary report is shown below. If the report isn't reviewed at test completion, it will be saved in the Documents folder.

Pay attention to the relative performance indices (RPI values) reported and analyzed by Scannerz. A significant change in RPI values may indicate developing problems with the media (both hard drives and SSDs). Changes in these values can indicate a significant performance deviation and yet not be reported by an S.M.A.R.T. analysis or be accompanied by errors or irregularities. In a hard drive it typically indicates that wear is beginning to take it's toll on the mechanical components of a hard drive while it still manages to function, and on an SSD it indicates that the memory cells are beginning to take longer to access, which often indicates  that either the disk is excessively full or the over provisioned area of the SSD is being depleted.


Basic Diagnostics Mode Testing Using Scannerz
 
Scannerz (not Scannerz Lite) comes with a feature introduced in version 1.7 known as Diagnostics Mode. In Diagnostics Mode, Scannerz will review the data from a Normal Mode test, and if needed, perform a battery of tests on not only the drive but the system to determine the exact nature of any problems. If Scannerz runs a test in Normal Mode and there are no errors or irregularities detected and the system seems to be running fine, Diagnostics Mode may not need to be used.
 
You will want to use Diagnostics Mode in any of the following conditions:
 

1. Irregularities or errors have been detected during a Normal Mode scan.
2. There is excessive data corruption occurring.
3. There are periodic system hangs or lock ups occurring, seemingly without warning.

An irregularity is an event that occurred during a test that Scannerz has flagged as taking an abnormally long amount of time to complete. Events that take too long are often indicators of existing or developing problems. Excessive data corruption may be occurring if the user frequently needs to use Disk Utility to perform repair operations on the drive. Periodic system hangs or delays may be caused by software problems, system faults, or drive/system timeouts. Going into details about these problems is beyond the scope of this document, however those interested in investigating them further may visit our page on advanced troubleshooting with Scannerz.
 
Diagnostics Mode allows essentially three options for testing:
 
Analyze Errors and Irregularities. This option is selected when you want to reevaluate any results from a Normal Mode scan.
 
Perform Interface Tests. If excessive data corruption is suspected of occurring this option allows the user to monitor data transfers occurring between the system and the selected volume. This test must be performed on a mounted volume that is capable of read and write operations. This test may also be used to help evaluate intermittent connections in bad connectors or cables or even logic board traces, observe system timeouts, and excessively long head parking events (mechanical hard drives only)
 
Perform Memory Tests. If there are periodic system hangs or lock ups occurring, seemingly without warning that can't be correlated to any drives connected to your system, this may be able to expose them. Calling this test a memory test is something of an understatement because it can also expose logic board faults as well.
 
To perform a Diagnostics Mode test, you select the media from the list of available drives, click on the tabbed item labeled "Diagnostics" and then click on the "Configure..." button. This will bring up the Diagnostics Mode test configuration dialog and is illustrated below.





After the tests are selected, you click on the "OK" button and can optionally open the logging window. Testing begins once the "Start Diagnostics" button is selected. The user may also stop diagnostics mode testing by clicking on the "Stop Diagnostics" button, which will terminate testing completely (it can't be re-started where it left off since most tests in this mode are quite specific.) A Diagnostics Mode session with the logging window up may appear similar to the following:




The Diagnostics Mode user interface has two progress bars as indicated above. The top bar indicates the overall progress of the current mode under test, and the bottom bar indicates the progress of all tests selected. The entries underneath the progress bars are as follows:
 
1. Confirmed Weak Block Counts. This indicates the media being scanned has confirmed weak blocks. These typically occur only on hard drives, but may occur on SSDs if the read time for a specific block is excessively slow. Confirmations here indicate that the problem is with the media (the hard drive or SSD).
 
2. Confirmed Bad Block Count. Confirmed bad blocks will be unreadable blocks or sectors on a hard drive or SSD. Once again, these will indicate that the problems are with the media, but in this case data will not be able to be recovered from the block or sector at all.
 
3. Seek Errors. These  will most likely only during tests of mechanical hard drives. If they occur on an SSD it usually indicates a faulty cable or connection or that the SSD is failing to evenly distribute memory blocks for usage, which can be a sign the drive is beginning to fail or has a firmware error. In Diagnostics Mode, Scannerz always checks seek values. A legitimate seek failure on a mechanical hard drive is a serious fault, and typically indicates a drive is failing.
 
4. Probable System Faults. These will occur during interface tests and memory tests and are generated by unrepeatable inconsistent irregularities or errors, indicating a likely intermittent connection or erratic system failure of some sort. Faults of this nature are usually related to the logic board, but they can also be induced by supply problems and in some cases, poorly seated and/or intermittent connections to the logic board.
 
5. Memory Errors. This will increment if bytes written and read to various location in memory are corrupt. This is a critical error and indicates memory is corrupt or dysfunctional, or the logic board is failing.
 
6. Interface Errors. This will increment if the data between the system and the targeted volume is corrupt. This is a critical error because it indicates data written to media and read back is corrupt. In most cases either the I/O cable connected to the drive is bad, or logic board components in the path between the logic board's I/O controller and the cable connector are intermittent.
 
Diagnostics Mode results can be viewed as Scannerz completes them in the log viewer and will also be contained in the associated log file. More details about Diagnostics Mode may be obtained by visiting our page on advanced troubleshooting with Scannerz.
 
Performing a Basic Drive Test Using Scannerz Lite
 
Scannerz Lite differs from Scannerz in the following ways:
 

• There are no Diagnostics Mode or Cursory Mode options.
• There is no report generation at the end of a test.
• Scannerz Lite simply reports a pass/fail status at the end of a test

 
 
Scannerz Lite is intended to be used by someone that simply wants to verify that their drive and system are functioning properly, and if they aren't, take the system in to a qualified professional for evaluation. It is not suited for distinguishing between a system problem and a drive problem, it cannot detect system timeouts or excessively long head parking events, and it can't evaluate potential interface, system bus, or memory problems. It can detect all these problems, but you won't be able to use the product to isolate them.
 
Functionally, Scannerz Lite operation is very similar to running a Normal Mode test in Scannerz, however instead of having a "Normal Scan" tab, the user interface has a single view on the lower section named "Scan Control and Test Results." Scannerz Lite does not have a logging window.
 
Most SCSC products are now placed in a folder named SCSC under the applications folder. Scannerz Lite is the only product that doesn't conform to this and is placed in a folder named "Scannerz Lite" under the applications folder.
 
Step by step instructions for performing a Scannerz Lite test are as follows:
 
1. Stop all other applications running on the system. This is required for older single core systems, but is highly recommended for all systems.
 
2. Navigate to the Applications → Scannerz Lite folder
 
3. Double click on the Scannerz Lite application icon. You will need to enter an administrative user ID and password before Scannerz Lite will start to launch as shown in the screenshot below.

4. Wait for Scannerz Lite to load all the system and drive information. If some drives are asleep it may take a bit longer for Scannerz Lite to start because it won't register the drives until they wake up. As the system and drive information is loaded, drop down windows will indicate whats going on and when complete, close.
 
5. After system and drive information is loaded, click on the “Scannerz Lite” menu item, and then select “Preferences” from the pull down and verify that the preferences are set properly (preferences are described in the users manual.)  This is illustrated in the screenshot below. Once you're familiar with Scannerz Lite, you probably won't need to do this often, but it can't hurt to check! The preferences in Scannerz Lite  are identical to those in Scannerz.

6. In the upper right hand corner of the Scannerz Lite user interface, select the drive or volume that you wish to test. Click on it and the information about the drive or volume will fill out in the upper left section of the user interface.

7. Click on the “Start Scan” button. A dialog will appear allowing you to rename and relocate the log file to a more convenient location with a more user friendly name. If this is not modified, Scannerz Lite will place it in the users "Documents" directory with the default name that Scannerz Lite created.
 
8. Once done a dialog will appear informing you to terminate all other applications. This will also be the last dialog that will allow you to back out of a test if you've made a mistake, such as selecting the wrong drive or volume. If “Cancel” is selected, you will return to the user interface, if you select “OK” the process will proceed.
 
9. If this is a continuation of a test from a previous session, then another dialog will appear giving you the option to continue where the last test left off or start all over again. The latter option will allow you to back out of a test that may have been initiated incorrectly.
 
10. After making the selection in item 9 above, testing will either begin or resume. The screenshot below illustrates Scannerz Lite  performing a seek scan on a RAID volume named "StripedUnit2."
 
When a hard drive or SSD is working properly (unless it's a very slow hard drive) the text field associated with the current test underway will likely change so rapidly the user won't be able to read it. When Scannerz Lite hits a bad or weak region, it will increment the error or irregularity counts as appropriate. If an error is detected, the unit needs servicing.  More details are provided in the Scannerz Lite manual. As stated previously, Scannerz Lite is not intended as a diagnostic tool, but as a verification tool.

At the completion of a test, Scannerz Lite simply produces a dialog indicating whether or not the unit passed or failed, as illustrated in the following screen shot:

Scannerz Lite is intended to be essentially a pass/fail tool. Log files and probing can allow you to evaluate a problem in more detail, but it's intended primarily for people that intend to let other people deal with any hardware problems they may be having.

Purchasing Scannerz
To purchase one of the  Scannerz packages, click on the Buy Scannerz Now button below.
 
Prices:

   $21.95 For Scannerz Lite

   $39.95 For Scannerz with FSE-Lite, Performance Probe, and Phoenix

   $49.95 For a Scannerz with FSE, Performance Probe,  and Phoenix

Thanks for your interest.
 
Questions? Comments? Suggestions?
 
Thank you for your interest. If you have any questions or comments, please feel free to drop us an e-mail using any of the contact addresses found using the About section of our web site which can be found at the top of this page.