Difference between tar and cp

Question

I have a microSD card to which I am writing a linux kernel and root filesystem.

If I create the root filesystem using tar then my board has no problem booting from the microSD card.

If I create the root filesystem using cp then the system hangs halfway during boot. The kernel boots OK but the system hangs when trying to start openssh.

TAR command:

sudo tar xfp ./debian-7.1-minimal-armhf-2013-08-25/arm*-rootfs-*.tar -C /media/rootfs/
sync

CP command:

sudo tar xfp ./debian-7.1-minimal-armhf-2013-08-25/arm*-rootfs-*.tar -C ./fileSystem/debian/
sudo cp  -p -r ./fileSystem/debian/* /media/rootfs
sync

Answer 1

I don't think cp is coping your symbolic links properly. Add -P (upper case) option to your cp command. That will ensure your symbolic links get copied properly. If on a mac use -a instead of -P.