.
The following is offered as a 'proof of principle' example for
prospective future modification of, or inclusion into Knoppix.
This idea has been employed with satisfactory outcome by me for
some time. This idea builds upon an already available feature
of the current Knoppix distribution.

Back-up & restore for 2 GB Knoppix 6.4.4 LiveUSB Persistent-store

0. When making a LiveUSB from the Knoppix LiveCD, allow 850 Mb for
persistent store; this leaves 350 Mb in /mnt-system for a com-
pressed persistent-store backup, update.tar.gz. Save the LiveCD.
If more than 1200 Mb is available and useful, then just preserve
a 2.5:1 ratio of persistent:compressed storage allotments.

1. Occasionally, while the LiveUSB is in active use, make a
compressed copy of the filesystem /KNOPPIX-DATA, name this
update.tar.gz, and then save* it in the /mnt-sytem/ directory,
or replace an older update.tar.gz there with a newer one.
*Hint: use or invent something like /etc/backup, see below.

2. When needed to restore the previous persistent-store info,
assuming the non-Live USB is at sdb1, use a LiveCD to move* what
now appears as
/media/sdb1/update.tar.gz one level to
/media/sdb1/KNOPPIX/update.tar.gz, then dismiss the LiveCD
and reboot the modified LiveUSB.
*Hint: using the LiveCD's PCManFM to drag & drop is the easy way.

3. After rebooting the modified LiveUSB & before shut-down, move*
/mnt-system/KNOPPIX/update.tar.gz back one level to
/mnt-system/update.tar.gz for safe-keeping until the next time
a restore is needed. Don't leave it in the /KNOPPIX directory.
*Hint: use the LiveUSB's PCManFM to drag & drop this time.

4. Back to step 1.
__________________________________________________ ______________

#!/bin/bash
#
# /etc/backup Note: make this root:root and executable
#
echo 'Saving update.tar.gz to /mnt-system.'
echo -e 'Patience; this may take a little time..\c'
#
cd /
tar -cf /tmp/update.tar KNOPPIX-DATA
cd /tmp
gzip update.tar
mv update.tar.gz /mnt-system
#
echo '..Done.'
#
exit 0