One disk and all filesystems have disappeared randomly

Hi,

my NAS has been working fine for months with only occasional reboots. Recently I went to access it and couldn't. Opened the GUI and found one of the filesystems status was 'missing'. I did all the available updates, and a couple of reboots to make sure, and still it's not happy. I have two disks "/dev/sda" and "/dev/sdb". /sdb is missing and doesn't appear when I do 'Scan'. Initially both filesystems were also missing, but after a little while the one for /sda has reappeared and just needed mounting. What can I do to 'find' /sdb? Physically it's an SSD, so it probably hasn't actually failed. I hope.

Thanks, Rob.

Ver 5.5.2-1 running on a RaspberryPi

Cancel that. I opened the box, wiggled all the cables and rebooted and everything seems to be back to normal again. How annoying...but a relief.