While snooping around the stock init script, I spotted a variable, home, in the mountdata function standing out from the crowd. After doing some quick tests, the preliminary results are summarised as follows,
Prerequisite: The persistent overlay (.img, .aes or .inf) being on the same partition as the KNOPPIX file.
Functionality: Loading a specific persistent overlay at the boot time.
Usage: knoppix home=/mnt-system/foobar/dummy
*The dirname and basename cannot contain any whitespace characters.
*The basename needs to be unique if there are more than one overlay files in the same folder because the suffix cannot be part of the argument.
JUNIPER ELECTRONICS NFX250-ATT-LS1
$250.00
Juniper Networks EX3300 EX3300-48P 48-Port Gigabit PoE+ Switch
$37.24
Juniper Networks EX3300 EX3300-48P 48-Port Gigabit PoE+ Switch
$59.95
Juniper EX3300-48P 48-Port 10/100/1000BASE-T (48 PoE+ ports) with 4 SFP+
$74.00
Juniper 48-Port PoE GbE Network Switch w/ 4-Port 10GB SFP+ Module EX4300-48P
$179.99
Juniper EX3300-48P, 48 Port PoE+ Gigabit Network Switch with RACK EARS, RESET
$46.99
Juniper EX4200-48PX 48-PORT 10/100/1000BASET PoE Ethernet Switch
$36.15
Juniper EX2300-48P 48-Port Gigabit Ethernet Switch PoE+ 4x SFP+ Power Cable
$104.40
Juniper Networks EX2300-C-12T Compact 12-Port EX2300-C Series Ethernet Switch
$300.00
JUNIPER SRX340 SERVICE GATEWAY APPLIANCE Tested/Working #73
$111.99