Hi all,

I'm dealing with a parity sync that is running extremely slowly — under 2MB/s with an estimated completion time of 80 days. Here's the sequence of events that led to this:

1. Parity drive failed and was replaced but sync was not ran.

2. The following day, Disk 5 showed as unmountable:Wrong or no file system.

3. I ran Check Filesystem in Maintenance Mode and applied the fixes, which appeared to resolve the issue.

4. Started a parity sync, but it ran at under 2MB/s and never improved after runnning for 5 Hours.

5. Stopped the sync and ran Check Filesystem in Mintenance Mode again — more errors were found.

6. Applied fixes again, but the same slow sync behaviour repeated.

It seems like there may be an underlying issue with Disk 5 that keeps resurfacing. Has anyone seen this pattern before? What would be the recommended next step?

Any help is appreciated. Thanks

tower-diagnostics-20260420-2253.zip

Disk5 keeps losing connection with the controller, check connections/replace SATA cable

Apr 20 22:49:34 Tower kernel: ata6.00: status: { DRDY }
Apr 20 22:49:34 Tower kernel: ata6.00: failed command: READ FPDMA QUEUED
Apr 20 22:49:34 Tower kernel: ata6.00: cmd 60/00:e8:40:fd:00/03:00:00:00:00/40 tag 29 ncq dma 393216 in
Apr 20 22:49:34 Tower kernel:         res 40/00:ff:00:00:00/00:00:00:00:00/00 Emask 0x10 (ATA bus error)
Apr 20 22:49:34 Tower kernel: ata6.00: status: { DRDY }
Apr 20 22:49:34 Tower kernel: ata6: hard resetting link
Apr 20 22:49:39 Tower kernel: ata6: SATA link up 1.5 Gbps (SStatus 113 SControl 310)
Apr 20 22:49:40 Tower kernel: ata6.00: configured for UDMA/33
Apr 20 22:49:40 Tower kernel: ata6: EH complete
Apr 20 22:49:40 Tower kernel: ata6.00: exception Emask 0x10 SAct 0x3ff0000 SErr 0x4090000 action 0xe frozen
Apr 20 22:49:40 Tower kernel: ata6.00: irq_stat 0x00400040, connection status changed
Apr 20 22:49:40 Tower kernel: ata6: SError: { PHYRdyChg 10B8B DevExch }
Apr 20 22:49:40 Tower kernel: ata6.00: failed command: READ FPDMA QUEUED
Apr 20 22:49:40 Tower kernel: ata6.00: cmd 60/00:80:40:21:01/01:00:00:00:00/40 tag 16 ncq dma 131072 in
Apr 20 22:49:40 Tower kernel:         res 40/00:01:00:00:00/00:00:00:00:00/00 Emask 0x10 (ATA bus error)
Apr 20 22:49:40 Tower kernel: ata6.00: status: { DRDY }
Apr 20 22:49:40 Tower kernel: ata6.00: failed command: READ FPDMA QUEUED
Apr 20 22:49:40 Tower kernel: ata6.00: cmd 60/00:88:40:22:01/04:00:00:00:00/40 tag 17 ncq dma 524288 in
Apr 20 22:49:40 Tower kernel:         res 40/00:01:00:00:00/00:00:00:00:00/00 Emask 0x10 (ATA bus error)

Edited April 20Apr 20 by Kilrah

Thanks. I'll look into this tonight when I get back from work.

22 hours ago, Kilrah said:

Disk5 keeps losing connection with the controller, check connections/replace SATA cable

Apr 20 22:49:34 Tower kernel: ata6.00: status: { DRDY }
Apr 20 22:49:34 Tower kernel: ata6.00: failed command: READ FPDMA QUEUED
Apr 20 22:49:34 Tower kernel: ata6.00: cmd 60/00:e8:40:fd:00/03:00:00:00:00/40 tag 29 ncq dma 393216 in
Apr 20 22:49:34 Tower kernel:         res 40/00:ff:00:00:00/00:00:00:00:00/00 Emask 0x10 (ATA bus error)
Apr 20 22:49:34 Tower kernel: ata6.00: status: { DRDY }
Apr 20 22:49:34 Tower kernel: ata6: hard resetting link
Apr 20 22:49:39 Tower kernel: ata6: SATA link up 1.5 Gbps (SStatus 113 SControl 310)
Apr 20 22:49:40 Tower kernel: ata6.00: configured for UDMA/33
Apr 20 22:49:40 Tower kernel: ata6: EH complete
Apr 20 22:49:40 Tower kernel: ata6.00: exception Emask 0x10 SAct 0x3ff0000 SErr 0x4090000 action 0xe frozen
Apr 20 22:49:40 Tower kernel: ata6.00: irq_stat 0x00400040, connection status changed
Apr 20 22:49:40 Tower kernel: ata6: SError: { PHYRdyChg 10B8B DevExch }
Apr 20 22:49:40 Tower kernel: ata6.00: failed command: READ FPDMA QUEUED
Apr 20 22:49:40 Tower kernel: ata6.00: cmd 60/00:80:40:21:01/01:00:00:00:00/40 tag 16 ncq dma 131072 in
Apr 20 22:49:40 Tower kernel:         res 40/00:01:00:00:00/00:00:00:00:00/00 Emask 0x10 (ATA bus error)
Apr 20 22:49:40 Tower kernel: ata6.00: status: { DRDY }
Apr 20 22:49:40 Tower kernel: ata6.00: failed command: READ FPDMA QUEUED
Apr 20 22:49:40 Tower kernel: ata6.00: cmd 60/00:88:40:22:01/04:00:00:00:00/40 tag 17 ncq dma 524288 in
Apr 20 22:49:40 Tower kernel:         res 40/00:01:00:00:00/00:00:00:00:00/00 Emask 0x10 (ATA bus error)

After many attempts I have worked out what the issue is. Turns out one of the ports on HBA controller is playing up. I swapped the cables into the other ports and the issue followed the port. I have now unplugged all drives from the port with the issue and the parity sync is now processing successfully but my cache port has no port to plug into. Time to buy new HBA Controller.