Using the tar --acls option to prevent the loss of ACLs during a backup

If you ever need to use tar to create a backup of either a file or a last two files:

[donnie@localhost ~]$ cd perm_demo_dir
[donnie@localhost perm_demo_dir]$ ls -l
total 0
-rw-rw-r--. 1 donnie accounting 0 Nov  5 20:17 file1.txt
-rw-rw-r--. 1 donnie accounting 0 Nov  5 20:17 file2.txt
-rw-rw-r--. 1 donnie accounting 0 Nov  5 20:17 file3.txt
-rw-rw-r--. 1 donnie accounting 0 Nov  5 20:17 file4.txt
-rw-rw----+ 1 donnie donnie     0 Nov  9 15:19 frank_file.txt
-rw-rw----+ 1 donnie donnie     0 Nov 12 12:29 new_file.txt
[donnie@localhost perm_demo_dir]$

Now, I'll do the backup without --acls:

[donnie@localhost perm_demo_dir]$ cd
[donnie@localhost ~]$ tar cJvf perm_demo_dir_backup.tar.xz perm_demo_dir/
perm_demo_dir/
perm_demo_dir/file1.txt
perm_demo_dir/file2.txt
perm_demo_dir/file3.txt
perm_demo_dir/file4.txt
perm_demo_dir...