Mercury Rack Pro/JMicron JMB393

[cnkenna]

Hi everyone, I'm hoping to get Direct I/O S.M.A.R.T. support added for the OWC Mercury Rack Pro, which uses a JMicron JMB393 port multiplier bridge.

Currently, StableBit Scanner cannot read the S.M.A.R.T. data for the drives inside this enclosure over USB. I have already tried enabling  UnsafeDirectIo  in the Advanced Settings and unchecking "Do not use Direct I/O when querying S.M.A.R.T.", but it still reports no data. However, the hardware is fully capable of passing the S.M.A.R.T. data through. I was able to successfully pull the complete health and temperature data for all the drives using  smartmontools  (v7.5) by manually specifying the JMicron port multiplier flags.

Here is my setup and how it responds:

• Enclosure: OWC Mercury Rack Pro (connected via USB)
• Drives: 3x Western Digital 8TB (WDC WD80EDAZ-11TA3A0)
• Working smartctl commands:
    •  smartctl -a -d jmb39x,0 /dev/pd15  (Successfully reads Drive 0)
    •  smartctl -a -d jmb39x,1 /dev/pd15  (Successfully reads Drive 1)
    •  smartctl -a -d jmb39x,2 /dev/pd15  (Successfully reads Drive 2)

Without the  ,0 ,  ,1 ,  ,2  port specification, the controller either returns a truncated response or fails with "scsi error aborted command".

It seems StableBit Scanner is missing the specific  jmb39x  port-switching commands that  smartmontools  uses to address the individual drives behind the bridge. Since  smartmontools proves the bridge allows the data through, would it be possible to add this JMicron port multiplier logic to Scanner's Direct I/O database?

Let me know if there's any additional info that I can provide!

[Christopher (Drashna)]

Make sure you're using the latest beta version.  There are some fixes: 
https://dl.covecube.com/ScannerWindows/beta/download/StableBit.Scanner_2.6.14.4133_BETA.exe

 

That said, the advanced settings, there are a couple of other options that may help (but try the beta first).  Namely, in the SMART section, check the "ignoreChecksum" option and restart the service.   If that doesn't help, try the "NoWMI" option, as well. 

 

If those don't work, head to https://stablebit.com/Contact and open a ticket there.  And then run the StableBit Troubleshooter, and use the ID number for that ticket.

StableBit Troubleshooter - Covecube - Wiki