Sorry, it took a while to find some time to get back to this. /var/log/udisks.log on a live system boot shows something interesting:
**** INITIAL ATA SMART POLL for /dev/sda (udisks-daemon:2964): udisks-daemon-WARNING: **: Daemon is inhibited -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/580112 Title: does not collect SMART data on live system -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
