#2207 Issue closed: checklayout indicates layout change if USB external drive mounted

Labels: support / question, fixed / solved / done

adatum opened issue at 2019-08-11 23:54:

  • ReaR version ("/usr/sbin/rear -V"): 2.4

  • OS version ("cat /etc/rear/os.conf" or "lsb_release -a" or "cat /etc/os-release"): Fedora 30

  • ReaR configuration files ("cat /etc/rear/site.conf" and/or "cat /etc/rear/local.conf"):
    REQUIRED_PROGS=( "${REQUIRED_PROGS[@]}" /home/test/Downloads/borg-linux64 )

  • System architecture (x86 compatible or PPC64/PPC64LE or what exact ARM device): x86_64

  • Firmware (BIOS or UEFI or Open Firmware) and bootloader (GRUB or ELILO or Petitboot): UEFI

  • Description of the issue (ideally so that others can reproduce it):

If rear mkrescue has been run, rear checklayout ; echo $? is non-zero indicating a layout change if a USB external drive is mounted which was not present at the prior run of rear mkrescue.

After the USB drive is unmounted, rear checklayout ; echo $? is zero again.

This is bad especially when rear checklayout || rear mkrescue is scheduled to run automatically (cron or systemd timer), or even if it's just run manually while a USB drive happens to be mounted.

This creates concern and confusion when rear recover notes that the device corresponding to the USB drive, /dev/sdb in this case, does not have a suitable target.
rear_usb_target

jsmeix commented at 2019-08-12 13:03:

It works as designed.

ReaR takes all mounted normal filesystems into account
so when there are changes in what is mounted, the disk layout has changed.

adatum commented at 2019-08-12 17:57:

In that case, is it possible to specify to ReaR not to monitor certain directories, eg. common mount points?

Actually, does it even have to be mounted or does anything in fdisk -l get considered by ReaR?

The use case must be common enough, yes? Does it make sense to create a new (incorrect) disk layout if a USB key/drive is plugged in? The result becomes unpredictable, especially if rear mkrescue is run on a schedule.

[Export of Github issue for rear/rear.]