JorgeB

Disk18 is failing, if there were no writes to the array since you replaced parity you can try to use the old one to rebuild disk18, if there were writes best bet is to use ddrescue on it.

There's something weird going on with the SATA controllers, syslog shows 4 different controllers, with 8 ports each, and then one of them fails to initialize: Nov 21 06:40:49 Tower kernel: ahci: probe of 0000:49:00.0 failed with error -22 Look for a BIOS update or try with a different Unraid/kernel version.

There's a pending sector, so likely a disk problem, you can run an extended SMART test to confirm.

I'm not seeing in the logs you doing what I asked: Nov 21 09:41:40 SaulGoodman emhttpd: import 31 cache device: (sdb) Crucial_CT512MX100SSD1_14260C762FF4 Nov 21 09:41:40 SaulGoodman emhttpd: import 32 cache device: (sdc) ADATA_SU800NS38_2I2420004148 These devices are currently part of a single btrfs pool and they are assigned to two different pools, unassign both start the array, assign both to the same pool, start array, do the pool device removal procedure, then you can do what you want to the other device. P.S. I see earlier that you did some cache replacement attempts, that is currently broken on v6.9+

Maybe someone else here has experience with that enclosure, I don't.

Please post the diagnostics.

If you really need longer than a meter best option it to use a SAS expander, cable from the HBA to the expander can be up to 10m, then 1m from the expander to the drives (for SATA drives).

Forgot to mention that you'll then have to access the server by the IP address, not the name, e.g. http://192.168.200.1

It wasn't, power cycle the server (don't just reboot) and post new diags.

It's fine for that.

In my experience a small difference is normal.

I found after posting this that with Unraid it only works for disk shares, it won't for user shares, likely because of FUSE, I still use it on a cache disk share.

Like mentioned having UEFI boot enable by default won't change anything for anyone booting legacy, if a new user boots with UEFI and then has trouble with VMs or any other issue he can try legacy boot, at least it's easier to get Unraid running for users with new hardware that now almost always comes with legacy boot disable.

Run a scrub on the pool, if all errors are correctable then run a balance to raid1, pool has dual data profiles, you should get a notification about that, if they are enable. Also see here for better pool monitoring.

By straight I just mean if it's direct connection or not, there's some info about that in the link I posted: You just need to do your own research, or try it, I don't one have to do it.

Note that to safely re-assign the device to the pool you need to do this: Stop the array, if Docker/VM services are using the cache pool disable them, unassign the remaining cache device, start array to make Unraid "forget" current cache config, stop array, now reassign both cache devices (there can't be an "All existing data on this device will be OVERWRITTEN when array is Started" warning for any cache device), re-enable Docker/VMs if needed, start array, then do the remove procedure.

That's expected, to remove a device from the pool you can do the standard pool device removal using the GUI.

Diags are after rebooting so we can't see what happened, but since SMART for disk6 looks OK and there were errors on multiple drives it suggests the disk wasn't the problem, so easiest way out of this is to do a new config and re-sync parity, if there are more read errors post new diags before rebooting.

You need to set manual IPv4 addresses for both, on the Ubuntu machine set to manual then input for example 192.168.200.1 , subnet mask use 255.255.255.0 or /24 depending on the available option, for the Unraid server the easiest way it to boot using the GUI option, you can then access the GUI using the local browser, set the IP to for example 192.168.200.2/24

Correct. It is OK but you must configure static IPs for both, since that way there's no DHCP server.

Try this: https://forums.unraid.net/topic/51703-vm-faq/?do=findComment&comment=557606

Ohh, and you also need to disable this as Unraid doesn't support secure boot.

You need to click on "Customize". Yep.

Did you enable UEFI boot on the flash drive? If not rename EFI- to EFI, or enable legacy boot in the BIOS.