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.
Apple Xserve A1009 14-Bay RAID Network Storage Array Enclosure
$249.99
Oracle 7085209 LSI MegaRAID SAS 9361-8i 1GB Cache 12Gbps SAS/SATA PCIe RAID Card
$28.20
DELL 4Y5H1 PERC H330 12GB SAS 6GB SATA PCI-E RAID CONTROLLER CARD
$38.49
Broadcom LSI 9400-16i Raid card SAS/SATA/NVME SFF-8643 SAS3416 PCIe 3.1 x8 HBA
$154.96
Inspur LSI 9300-8i Raid Card 12Gbps HBA HDD Controller High Profile IT MODE
$15.98
LSI MegaRAID 9361-8i 12Gb PCIe 8-Port SAS/SATA RAID 1Gb w/BBU/CacheVault/License
$39.95
ORICO Multi Bay RAID Hard Drive Enclosure USB 3.0/ Type-C For 2.5/3.5'' HDD SSDs
$86.99
LSI MegaRAID 9361-8i 12Gbps PCIe 3 x8 SATA SAS 3 8 Port RAID + BBU & CacheVault
$39.00
ACASIS 2.5/3.5 inch 2 Bay SATA USB 3.0 Hard Drive Disk HDD SSD Enclosure 4 RAID
$58.99
Lenovo 930-16i PCIe SAS RAID Controller FRU P/N: 01KN508 Tested Working
$149.99