I am running 6.3.2 and Disk 10 failed on a monthly parity check.

 

I replaced the failed disk with a new one, and reasigned the new disk

 

The disk rebuild was started but the new disk has failed too, and it appears that the rebuild operatin was cancelled?

 

Please find attached diagnostics file

tower-diagnostics-20170302-0617.zip

I'm answering from my phone where I can't look at the diagnostic file. But very much sounds like the most common reason for drives dropping offline, bad or lose sata cabling. Likely all your drives are fine. It only takes a tiny nudge to ever so slightly disrupt the drives communication with its controller. It may appear to work for a while, but eventually the connection will cause the drive to kick, often under heavy use mine a parity check. Connections under tension or in the vibrating environment inside the server, can also work themselves loose, causing the sane symptoms, and often swapping such a drive causes the owner to disrupt other cables which causes a second drive to drop.

 

Unfortunately fixing the cabling issues won't undo the drive(s) being kicked from your array. But once you get the disk or disks rebuilt (or do a new config), it should help avoid repeat performances.

 

Note that locking cables and drive cages are highly recommended to help avoid this type of cabling hell.

Looks like another typical SASLP/SAS2LP issue, SASLP in your case, disable VT-D if not needed, look for a bios update and/or try the controller in a different slot if available.

All disks in 5x3 cages, with lockable cables. I have been there with standard SATA connectors!

 

I have uuplugged and reseated the cable for Disk 10, and my replacement disk is rebuilding again.