Re: [smartmontools-support] smart Airflow_Temperature_Cel attribute value on Micron RealSSD

[Christian F. <Chr...@t-...>]

Janardhan Molumuri wrote:
> Thanks for your response, Christian.
>
> >> smartctl -r ioctl,2 -i -H -d sat+megaraid,9 /dev/bus/0
> Attaching the output. smart status check returned -1.
> ...
> REPORT-IOCTL: Device=/dev/bus/0 Command=SMART STATUS CHECK
>   Input:   FR=0xda, SC=...., LL=...., LM=0x4f, LH=0xc2, DEV=...., CMD=0xb0
>   [ata pass-through(16): 85 06 2c 00 da 00 00 00 00 00 4f 00 c2 00 b0 00 ]
> sat_device::ata_pass_through: scsi_pass_through() failed, errno=38 [ATA return descriptor not supported by controller firmware]
> REPORT-IOCTL: Device=/dev/bus/0 Command=SMART STATUS CHECK returned -1 errno=38 [ATA return descriptor not supported by controller firmware]
> SMART overall-health self-assessment test result: FAILED!
> Drive failure expected in less than 24 hours. SAVE ALL DATA.
> Failed Attributes:
> ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE
> 190 Airflow_Temperature_Cel 0x0023   019   033   069    Pre-fail  Always   FAILING_NOW 19 (Min/Max 17/33)

We have 3 issues here:

- LSI MegaRAID firmware does not support SAT ATA return descriptor which 
means that the (boolean) result from SMART RETURN STATUS command be read 
from the drive.

- smartctl reports this fact only in debug output (I fixed this in r3920).

- Drive returns bogus normalized VALUE and THRESHold for attribute 190.

If SMART RETURN STATUS does not work, smartctl checks the attribute 
table instead. Therefore smartctl reports a FAILED SMART test result 
which is possibly not identical to the actual status returned by the drive.

>
> >>None of the specs or previous sample outputs from Micron RealSSDs 
> include attribute 190.
> What is the best way out in these cases to detect the health status of 
> the disks? Is there a flag or something to detect the value type 
> (normalized vs real)?

No, the value in the normalized VALUE field should always be normalized :-)

Could you possibly connect this drive to some Motherboard controller or 
other non-RAID controller and repeat the test?

Thanks,
Christian