exFAT SSD network share intermittent issues

Installing and Using OpenWrt
1

Has anyone tried to network-share an exFAT SSD with Samba or SFTP ? If so, were you able to stream movies from it without any issues?

My setup is OpenWRT running on Zyxel Armor Z2, with a Sandisk external SSD into the USB port. The drive is formatted with exFAT and works fine when connected to a laptop, both Mac and Win.
But connected to the router, under OpenWRT it appears to randomly disconnect. Happens with both Samba and SFTP.

Looking at the kernel log I see a lot of this messages:

482.882664] sd 0:0:0:0: [sda] Optimal transfer size 2097152 bytes
[  482.900666]  sda: sda1
[  482.902600] sd 0:0:0:0: [sda] Attached SCSI disk
[  484.102426] usb 4-1: USB disconnect, device number 8
[  484.103809] sd 0:0:0:0: [sda] Synchronizing SCSI cache
[  484.698281] sd 0:0:0:0: [sda] Synchronize Cache(10) failed: Result: hostbyte=0x07 driverbyte=0x00
[  485.168124] usb 4-1: new SuperSpeed Gen 1 USB device number 9 using xhci-hcd
[  485.206503] scsi host0: uas
[  486.459707] scsi 0:0:0:0: Direct-Access     SanDisk  Extreme Pro 55AF 1087 PQ: 0 ANSI: 6
[  486.462939] scsi 0:0:0:1: Enclosure         SanDisk  SES Device       1087 PQ: 0 ANSI: 6
[  486.471970] sd 0:0:0:0: [sda] 7813971617 512-byte logical blocks: (4.00 TB/3.64 TiB)
[  486.475106] sd 0:0:0:0: [sda] Write Protect is off
[  486.482765] sd 0:0:0:0: [sda] Mode Sense: 37 00 10 00
[  486.484820] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, supports DPO and FUA
[  486.487604] sd 0:0:0:0: [sda] Optimal transfer size 2097152 bytes
[  486.510357]  sda: sda1
[  486.514445] sd 0:0:0:0: [sda] Attached SCSI disk
[  487.699877] usb 4-1: USB disconnect, device number 9
[  487.702856] sd 0:0:0:0: [sda] Synchronizing SCSI cache
[  488.308487] sd 0:0:0:0: [sda] Synchronize Cache(10) failed: Result: hostbyte=0x07 driverbyte=0x00
[  488.808473] usb 4-1: new SuperSpeed Gen 1 USB device number 10 using xhci-hcd
[  488.846667] scsi host0: uas
[  490.070521] scsi 0:0:0:0: Direct-Access     SanDisk  Extreme Pro 55AF 1087 PQ: 0 ANSI: 6
2

The first thought I have is that exFAT is a 64bit format that is a bridge between Linux with its ext4 and Windows with its NTFS and the router is only a 32bit device. Usually when you connect USB memory devices to embedded linux tech they need to be formatted to FAT32.

You could try this theory by format the SSD with FAT to see if it makes any difference.

Or make a real NAS connected to the network.

3

I moved the drive to the USB 2.0 port, watched an entire movie and had no issues so far.
So it appears it has something to do with USB 3.0