for months now I've been doing physical backup from an Ubuntu Server 20.04 to USB drives I swap out and take off site. No rocket science, I plug in the drive, mount the block device, typically /dev/sdb1 and I'm off.
The drives have NTFS partitions, and are 4GB in size. Now since yesterday and some routine updates neither of my two identical USB drives will get a block device created on plugging it in to the Linux host. Both show up fine in Windoze. I went so far as to reformat one, both gain as NTFS and once as xfat. Neither action resulted in any changed behaviour when plugging it into the Ubuntu host.
The block device /dev/sdb eventually show up after plugging it in - but only after a very long time.
# file /dev/sdb
/dev/sdb: block special (8/16)
but I fdisk can't "see" it:
# fdisk /dev/sdb
Welcome to fdisk (util-linux 2.34).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
fdisk: cannot open /dev/sdb: No such file or directory
Nothing shows with lsblk or blkid I guess since the block device is never created.
Any suggestions what to try to get this working again?
try setting up rsync to make your backups to another computer.