[smartmontools-support] The kernel warnings in Solaris you are seeing

[Brian B. <br...@pu...>]

Hello all,

I was looking for an answer in the same vein as the question posted by
Derek Lambert, but that said I can answer his.

What is happening is here:

...

    SMART support is: Available - device has SMART capability.
    SMART support is: Enabled

...

Your drive is responding to a mode sense command page called
Informational Exceptions. The response from your drive is going to
dictate what happens next. So since you are getting SMART available
and enabled, you are inviting the next request from the smart tools
which is an ATA_PASSTHROUGH. You will typically see the opcode 0x85
which is the 16 byte SCSI version of the command that you are seeing
0xA1. If your drive can answer SMART is Available but Disabled you
will likely find that the kernel warnings will stop.

Here is the ESX variant of your Solaris issue:
https://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1036874

The answer to the Informational Exceptions is key. So, for example,
PURE LUNs from our array:

[root@init101-11 ~]# sg_modes -p 0x1c /dev/sg1
    PURE      FlashArray        8888   peripheral_type: disk [0x0]
Mode parameter header from MODE SENSE(10):
  Mode data length=28, medium type=0x00, WP=0, DpoFua=0, longlba=0
  Block descriptor length=8
> Direct access device block descriptors:
   Density code=0x0
 00     3e 7f ff ff 00 00 02 00

>> Informational exceptions control, page_control: current
 00     1c 0a 08 00 00 00 00 00  00 00 00 00

It is the presence of the 08 that is key. If you run that command and
you see 00 there it probably explains what you see. Here is the
smartctl on the PURE LUN:

...
Device supports SMART and is Disabled
Temperature Warning Disabled or Not Supported
....

I can give you more details if you need them.

Thanks,
Brian