I got this error while restoring my backup of the rootfs:

I had done:

tar -jxvvf /home/droidzone/documents/rootfs.tar.bz2

Since I was using the verbose option -vv, I couldnt notice what the error mesage was.

I tried the ignore error option with:

tar -ignore-command-error -ignore-failed-read -jxvvf /home/droidzone/documents/rootfs.tar.bz2

But the error happened again.

Removing the verbose option showed the error:

[email protected]:/# tar -ignore-command-error -ignore-failed-read -jxf /home/droidzone/documents/rootfs.tar.bz2 
tar: dev/pts/2: Cannot mknod: Operation not permitted
tar: dev/pts/0: Cannot mknod: File exists
tar: dev/pts/1: Cannot mknod: File exists
tar: dev/pts/ptmx: Cannot mknod: File exists

So if you have block devices and try to restore to them, this error can happen. And it’s in most cases safe to ignore.