Power is not a problem - both disks in external HDD 2 Bay HDD Case (see https://fantec.com/product/fantec-qb-x2us3r/) with external power supply. The disks are SATA (1x WD RED and 1 x WD Green) - from the external case perspective configured as JBOD but one of the BTRFS partitions is configured as Raid1 over these 2 disks (as one disk is larger the rest of the space is another BTRFS partition with single disk)
Below is the extract from the log after restart filtering out ‘usb’. There is problem with UAS which was reported earlier in Rozbitý USB3 UAS po update (restartu) na 3.11.3 but otherwise I cannot see anything else from the logs. There are no USB related events in the log when the disks are “remapped”. When I disconnect the case then there are no messages in the log either. When I connect it back I can the messages that new USB Mass Storage device detected and that the UAS is not available.
The external case worked fine when I was on 3.x version - but at that time I had a single disk inside so there was a change there too. I can try to remove the second disk as the data is mirrored to rule it out.
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 3.120600] usbcore: registered new interface driver usbfs
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 3.120626] usbcore: registered new interface driver hub
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 3.120652] usbcore: registered new device driver usb
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.478984] orion-ehci f1058000.usb: EHCI Host Controller
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.484412] orion-ehci f1058000.usb: new USB bus registered, assigned bus number 1
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.492048] orion-ehci f1058000.usb: irq 40, io mem 0xf1058000
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.521334] orion-ehci f1058000.usb: USB 2.0 started, EHCI 1.00
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.535646] xhci-hcd f10f0000.usb3: xHCI Host Controller
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.540978] xhci-hcd f10f0000.usb3: new USB bus registered, assigned bus number 2
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.548548] xhci-hcd f10f0000.usb3: hcc params 0x0a000990 hci version 0x100 quirks 0x0000000000010010
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.557817] xhci-hcd f10f0000.usb3: irq 46, io mem 0xf10f0000
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.576942] xhci-hcd f10f0000.usb3: xHCI Host Controller
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.582280] xhci-hcd f10f0000.usb3: new USB bus registered, assigned bus number 3
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.589789] xhci-hcd f10f0000.usb3: Host supports USB 3.0 SuperSpeed
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.596279] usb usb3: We don't know the algorithms for LPM for this host, disabling LPM.
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.612469] xhci-hcd f10f8000.usb3: xHCI Host Controller
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.617798] xhci-hcd f10f8000.usb3: new USB bus registered, assigned bus number 4
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.625356] xhci-hcd f10f8000.usb3: hcc params 0x0a000990 hci version 0x100 quirks 0x0000000000010010
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.634620] xhci-hcd f10f8000.usb3: irq 47, io mem 0xf10f8000
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.648433] xhci-hcd f10f8000.usb3: xHCI Host Controller
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.653772] xhci-hcd f10f8000.usb3: new USB bus registered, assigned bus number 5
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.661279] xhci-hcd f10f8000.usb3: Host supports USB 3.0 SuperSpeed
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.667767] usb usb5: We don't know the algorithms for LPM for this host, disabling LPM.
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 4.684014] usbcore: registered new interface driver usb-storage
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 5.014151] usb 3-1: new SuperSpeed USB device number 2 using xhci-hcd
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern warning kernel[]: [ 5.042464] usb 3-1: USB controller f10f0000.usb3 does not support streams, which are required by the UAS driver.
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern warning kernel[]: [ 5.052765] usb 3-1: Please try an other USB controller if you wish to use UAS.
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 5.060091] usb-storage 3-1:1.0: USB Mass Storage device detected
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 5.066286] usb-storage 3-1:1.0: Quirks match for vid 152d pid 9561: 4000000
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 5.073397] scsi host2: usb-storage 3-1:1.0
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 8.952864] usbcore: registered new interface driver uas
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 15.535682] usbcore: registered new interface driver ums-alauda
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 15.542004] usbcore: registered new interface driver ums-cypress
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 15.548418] usbcore: registered new interface driver ums-datafab
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 15.554837] usbcore: registered new interface driver ums-freecom
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 15.561269] usbcore: registered new interface driver ums-isd200
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 15.567731] usbcore: registered new interface driver ums-jumpshot
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 15.574258] usbcore: registered new interface driver ums-karma
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 15.580569] usbcore: registered new interface driver ums-sddr09
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 15.586988] usbcore: registered new interface driver ums-sddr55
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 15.593361] usbcore: registered new interface driver ums-usbat
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 15.600930] usbcore: registered new interface driver usbserial
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 15.606822] usbcore: registered new interface driver usbserial_generic
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 15.613409] usbserial: USB Serial support registered for generic
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 19.556793] usbcore: registered new interface driver qcserial
2020-08-13T13:33:12+02:00 2020-08-13T13:33:12+02:00 omnia kern info kernel[]: [ 19.562629] usbserial: USB Serial support registered for Qualcomm USB modem