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.
New Precision DWDM SFP+ 10G 80km Tunable Transceiver 50GHz C-Temp DWDM-SFP10G-C
$90.00
LOT OF 20 Genuine Cisco SFP-10G-SR V03 10GBASE-SR SFP+ Transceiver Module
$95.00
GENUINE CISCO DS-SFP-FC32G-SW SFP NEW SEALED SEE PHOTOS SHIPS FREE
$69.99
Original CISCO SFP-10G-SR V03 10-2415-03 850nm 10GBASE-SR SFP+ Multi mode Module
$6.80
Brand New Cisco GLC-LH-SMD 1000BASE-LX/LH SFP Module 1310nm 10km SMF LC
$12.99
Precision PRE-SFP-TMI-CSCO 1GB BASE-T RJ-45 SFP Transceiver - For Cisco
$2.89
CISCO SFP-10G-LR SFP TRANSCEIVER MODULE GBIC 10G 10GB SFP - 1 Year Warranty
$39.99
GENUINE Cisco SFP-10G-SR V03 SFP+ GBIC Transceiver Module 10-2415-03
$6.80
New HP HPE Aruba J9150D 10G SFP+ LC SR 850nm 300m MMF XCVR Transceiver Module
$45.99
SFP-10G-SR CISCO 10G SR SFP+ C-CLASS TRANSCEIVER 10 PACK
$99.00