cloned sd card is not booting

[Robert Moskowitz]

This is a Fedora arm problem, but probably more experience with dd and 
sd cards here...

SO I boot my Cubieboard2 from microSD.  I grabbed 8 16GB cards from the 
bin at the MicroCenter checkout counter.  They work fine for building 
F21 arm boots, but I am getting far enough into the process that if I do 
something wrong, I don't want to go all the way back to the beginning.  
I rather clone the card, play around, and soforth. So I tried using:

sudo dd if=/dev/sdb of=/dev/sdc bs=4096 conv=notrunc,noerror; sync

the target sd card has been previously use.  The copy fails in use as 
follows:

          Mounting Configuration File System...
[  OK  ] Mounted Configuration File System.
[  OK  ] Found device 
/dev/disk/by-uuid/1dc878de-92d2-4a66-b352-f055a32473b9.
[  OK  ] Started dracut initqueue hook.
[  OK  ] Started Show Plymouth Boot Screen.
[  OK  ] Reached target Paths.
[  OK  ] Reached target Basic System.
          Starting dracut pre-mount hook...
[  OK  ] Reached target Remote File Systems (Pre).
[  OK  ] Reached target Remote File Systems.
          Starting File System Check on 
/dev/disk/by-uuid/1dc8...f055a32473b9...
[   13.911063] systemd-fsck[368]: _/: The filesystem size (according to 
the superblock) is 3587707 blocks
[  OK  ] Started dracut pre-mount hook.
[   13.919598] systemd-fsck[368]: The physical size of the device is 
3548795 blocks
[   13.937109] systemd-fsck[368]: Either the superblock or the partition 
table is likely to be corrupt!
[   13.944962] systemd-fsck[368]: _/: UNEXPECTED INCONSISTENCY; RUN fsck 
MANUALLY.
[   13.950853] systemd-fsck[368]: (i.e., without -a or -p options)
[  OK  ] Started File System Check on 
/dev/disk/by-uuid/1dc87...2-f055a32473b9.
          Mounting /sysroot...
[   14.483857] random: nonblocking pool is initialized
[   14.571964] EXT4-fs (mmcblk0p3): bad geometry: block count 3587707 
exceeds size of device (3548795 blocks)
[FAILED] Failed to mount /sysroot.
See 'systemctl status sysroot.mount' for details.
[DEPEND] Dependency failed for Initrd Root File System.
[DEPEND] Dependency failed for Reload Configuration from the Real Root.
[  OK  ] Stopped dracut pre-pivot and cleanup hook.
[  OK  ] Stopped target Initrd Default Target.
[  OK  ] Stopped dracut mount hook.
[  OK  ] Reached target Initrd File Systems.
[  OK  ] Stopped target Basic System.
[  OK  ] Stopped target System Initialization.
          Starting Emergency Shel
Generating "/run/initramfs/rdsosreport.txt"


Entering emergency mode. Exit the shell to continue.
Type "journalctl" to view system logs.
You might want to save "/run/initramfs/rdsosreport.txt" to a USB stick 
or /boot
after mounting them and attach it to a bug report.


:/#

=======================================================

I put the card back in my build system and looked at it with Gparted 
which shows the whole drive as unallocated, even though the system 
successfully mounted /boot (but not /).

So the question is:  HOw better can I clone the card?  SDFormatter in 
Windows is one suggestion, but I don't want to have to jump over to the 
family XP system.

thanks