User manual

Using S.M.A.R.T. Disk Monitor 105
SANTOOLS® is registered in US Patent and Trademark Office No 3,107,854 All rights reserved.
When to Reassign Blocks (SCSI family disks only)
SMARTMon-UX makes it easy for you to know when you have blocks that must be forcibly reassigned.
Just run either the self-test (-steb , or -scrub family) commands, and they will report if any blocks have
unrecovered errors that should be reassigned.
The advantage of using the -steb test is that this is a built-in test and does not consume any host bandwidth.
The test can take 30 minutes to several hours depending on the disk drive. This is a built-in test that is initiated by
sending a single SCSI command. Once the test is invoked, SMARTMonUX returns and lets you know whether the
test was successfully launched. As the test is a background test, it can be run on any and all disk drives, even while
I/O is going on. The tests will temporarily suspend to service I/O requests from applications running on your host.
The disadvantage of the -steb , and -stsb tests is that they only report the first bad block found, (-stsb
might not report any bad blocks) so if you have multiple bad blocks you run the test, reassign, and repeat.
Our -scrub family of commands makes a single pass through the disk and returns a list of all blocks that had
problems along with the sense information as shown above. This command is also safe to run on your host, but it
does consume bandwidth, and the test may also take hours. The -scrub command causes every block in the disk to
be read while recording sense information and error codes, which it reports to the operator. He/she will then be able to
see all errors and, if required, remap all of them without having to endure multiple passes.
We currently do not provide a mechanism to reassign blocks on SATA / ATA disks.
1.32 Self-Test Diagnostics - ANSI
In release 1.21, we introduced the ability for the user to initiate self-tests. SANtools-specific self-test diagnostics
were added in version 1.26. Both have strengths and weaknesses, and you should consider which one (or both) of
these tests would be best for you to run in your environment.
Before going further, it is important to understand that the various ANSI specifications for peripherals mandate several
types of self-tests. One is mandatory (unless your peripheral is ancient), many are optional. If you send a certain type
of self-test to a peripheral that does not support it, then the device is obligated to reject the command. Our software
will not tell you ahead of time that a particular device supports a certain self-test function. Well will however, report if it
was rejected, or accepted. The ANSI self-test specifications define foreground and background self tests, as well as
sort and long self tests that may run for a few seconds to a few hours.
Some self-tests, like a foreground test, will lock up your peripheral while it is running.. Others will affect performance
by only a few percentage points. Per the spec, self-tests can be aborted, and you can report ongoing status at any
time. Per real-life situations, we have found that some peripherals and firmware revisions do not correctly allow
self-tests to be terminated nor do all of them allow the user to request an update while they are running. The SCSI
spec. states that the standard self-test is mandatory, and the short and extended self-tests are optional. If your
particular device does not support your selected test, the program will notify you after you attempt to initiate the test.
Once smartmon-ux instructs your device to begin the test, our program continues processing other commands which
you may have given it. Your device runs the test independently of smartmon-ux and will only end if either the test
completes, terminates because an error is found, or you abort the test (via the -str command).
Self-Tests for Tapes, Autochangers, and everything but Disk Drives
SMARTMonUX will allow you to run the embedded self-tests that manufacturers include in their firmware. A great
number of our customers buy our software so they can do nothing more than test peripherals and tapes on
non-windows operating systems.
Self-Tests for Disk and Random-access Devices
If you have SCSI, SAS, or fibre channel disks, then there are no constraints (except under Apple OS X, due to lack of
pass-though support for SCSI peripherals). If, however, you have ATA or SATA disk drives, then there are limitations
under several operating systems. We provide full support for the native ATA/SATA self-tests under Windows only at
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