Thanks for the link
I have now labeled my USB backup disk:
# /sbin/e2label /dev/sda3 USB-backup
The two relevant lines in /etc/fstab:
/dev/sda3 /media/usbdisk1 ext3 defaults
/dev/sda1 /media/usbdisk ext3 pamconsole,noatime,sync,exec,noauto,managed 0 0
I changed to:
#/dev/sda3 /media/usbdisk1 ext3 defaults
LABEL=USB-backup /media/usbdisk ext3 defaults
/dev/sda1 /media/usbdisk ext3 pamconsole,noatime,sync,exec,noauto,managed 0 0
I hope it works, but I am little concerned whether these changes to /etc/fstab will "survive" various events and system changes.