[SOLVED] 6.8.0 - fstrim: /mnt/cache: the discard operation is not supported


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Recently upgraded to 6.8.0 (12/28)


I have had The "Dynamix SSD Trim" plugin installed for a long time w/o any issues/email warnings.  Since the install of 6.8.0 I've started getting the error message in the subject.  fstrim: /mnt/cache: the discard operation is not supported


The only recent hardware changes was adding an external controller card so I could expand unRAID by adding two more drives. I did not move the Cache SSD to the external controller, so it should not have been impacted at least AFAIK.  As a troubleshooting step I had one free port on the MB controller so I swapped my Cache SSD to that, but no change in error. Just for information, the card I bought is: https://www.ebay.com/itm/162958581156?ViewItem=&item=162958581156 (but only two 4TB Red's attached). This was installed ~1mo before upgrading to 6.8.0 from 6.7.2


Cache/App Drive is a Samsung 860 1TB 



The Motherboard has 6 Brown SATA and two Grey SATA connectors. The SSD was connected to the ASmedia Grey, but currently I swapped it to the Brown.


AMD SB950 controller :

6 x SATA 6Gb/s port(s), brown
Support Raid 0, 1, 5, 10
ASMedia® PCIe SATA controller :

2 x SATA 6Gb/s port(s), gray
2 x eSATA 6Gb/s port(s), red,


I am attaching diagnostics, however the server was just rebooted, and I attempted to run the fstrim command manually after the starting it back up.


Any help would be appreciated.





Edited by Dmtalon
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1 minute ago, johnnie.black said:

On the diags posted SSD is still on an Asmedia controller, and it is one of the older revs where trim is known to have issues, try one of AMD ports.

oh man... maybe I moved the wrong cable.  I'll walk back down there.  I hope that's it, but what a silly mistake.

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Well, what do ya know. I could have fixed this by actually swapping the right cable on try #1.   In a lame attempt to redeem myself, the cables I use are hard to get off when there's two because of the metal clips. Both popped off at the same time, causing me to somehow lose track of the right cable.  I have no excuse, lame or otherwise, as to why I didn't verify once I moved it  <sigh>  :)

Thanks @johnnie.black


root@:~# fstrim -v /mnt/cache
/mnt/cache: 820.5 GiB (880946581504 bytes) trimmed

Edited by Dmtalon
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