JorgeB

Not many 4 port options, there's the old Adaptec 1430SA which still works fine (but not good for SSDs), and newer ones with 4 or 5 port based on the JMB585 chipset, these are rather recent but all indications so far is that they are reliable, though you can usually get a used 8 port LSI HBA for around the same price.

Those SIL controllers are quite old and not recommended for some time, still it could be a cable/connection issue, try replacing the SATA cable, or swapping ports with one of the disks.

It should, re: snapshots, try to keep as few snapshots as possible, the more snapshots you have the slower the filesystem will become, low single double digits are recommended.

Not for this one, but transfers are mostly from the large SSD cache pool, HDD array is for streaming video only, so normal HDD read speeds are enough.

Just above that one, the "single" profile.

That's relatively normal and usually no reason for concern, that's why it appears as "info", not "warning" or "error", and it usually goes way by itself, doubt that's the reason for the reported issues.

https://forums.unraid.net/topic/46802-faq-for-unraid-v6/?do=findComment&comment=480421

Original pool was using single profile for data, so it could use full capacity, but like raid0 without redundancy.

That should always work, for any case, possibly wrong or missed command entered, but glad it's fixed.

No, still not correct, do this instead: stop array wipefs -a /dev/sdX1 wipefs -a /dev/sdX replace X with cache1, then repeat both for cache2, after that start array and re-format pool.

https://forums.unraid.net/topic/60231-amd-gpu-reset-bug/?do=findComment&comment=811771

Couple of more observations, regarding hardware, and obviously besides a fast device/pool, the only other thing you want is an high clock CPU with a fast single thread rating, Samba is single threaded, so e.g. a fast dual core CPU is better then a low clock 8 core Xeon. Also, and since 99% of the time my transfers to this server are in the other direction, from Unraid, not to Unraid, it's been some time since I've paid attention to write speed, fuse overhead appears to be more pronounced with v6.8.x compared to v6.7.x, did a quick test and currently I'm getting more like 700MB/s write speed to a user share, I remember getting around 800/900MB/s with v6.7.x. User share vs disk share

Try a different USB HUB? Powered on would be better.

Check filesystem on disk11: https://wiki.unraid.net/Check_Disk_Filesystems#Checking_and_fixing_drives_in_the_webGui Rebuilding a disk won't fix filesystem corruption.

Supermicro X11SSM-F, G4560, 6 SSD RAID5 cache pool

Delete network.cff and network-rules.cfg also on flash/config and reboot, if still nothing please post new diags.

Diags are after rebooting so we can't see what happened but disks look fine, so likely some connection/power issue. Yes, format is never part of a rebuild/replace. Check filesystem on the emulated disk, if it's fixable and it mounts correctly and data looks OK you can then rebuild on top, you can also re-sync parity at the same time, but suggest replacing/swapping cables (both SATA and power) on both disks first to rule that out.

If disabling power states didn't help it's likely a hardware/bios problem, either the board or the NVMe device.

Default is still usually not the correct setting needed for stability with Linux.

Yes, that is overclocking.

Pool wasn't created correctly, only one device is being used and there are multiple profiles, make sure you wipe both cache devices before formatting, if you get an error with blkdiscard on any of them wiping won't work, e.g., if the controller doesn't support trim.

After all data is backed up, stop array and type: blkdiscard /dev/sdX Replace X with both devices ID, one at a time, after that start the array and you'll have the option to format the pool.

There's corruption on the cache filesystem, with btrfs it's best to backup data, re-format pool and restore data, also a good idea to re-create docker image at the same time.

Please post the complete diagnostics: Tools -> Diagnostics

Don't know, but not the first time I see similar errors with AMD based systems, BIOS update might help.