Just get rid of the commment line added by knoppix. If you get rid of the comment the line after it will not be changed on startup. Hopefully this helps this problem drove me nuts until i found the solution.
I installed 3.4 on HD last night, and customized it to suit my needs. I had been using 3.3 for a while, and it's worked wonderfully for me. Anyway, I fixed up fstab to mount my (pre-existing) /home and /data partitions, set up my static IP, added rc files for the services I need, etc... all is groovy. After a re-install, all of my changes in /etc are gone! fstab is overwritten, system attempts to use DHCP to get network settings (and fails...), rc3.d and rc5.d directories are empty again...
There's gotta be a script somewhere that is doing this, but I can't find it. Any ideas?? I can reset everything, but if my wife ever reboot's the machine, she's toast! Of all the config tweaks to loose, fstab has to be the worst...
Just get rid of the commment line added by knoppix. If you get rid of the comment the line after it will not be changed on startup. Hopefully this helps this problem drove me nuts until i found the solution.

HPE Synergy 480 Gen 10 Blade Server | 96GB Ram | No HDDs | Complete Otherwise
$500.00
Dell PowerEdge FX2s + 8x FC430 Blades 16x E5-2630v4 160 Cores Rails No PSU/RAM
$699.00
NETAPP HCI NAF-1701 SuperMicro Server 4X BLADE H410C 8X GOLD 5120 - 4X S25G NICs
$1999.97
Lot of 3 Dell PowerEdge Blade Server HHB005 x2 HHB006 x1
$256.49
LOT (8) Cisco UCS UCSB-B200-M5 2x6248R 24 core 3.0G 24x64g DDR4-2933 ram
$112000.00
Dell PowerEdge VRTX Rackmount Chassis w/4x PSUs 2x CMC Modules
$399.98
Dell PowerEdge FX2 FX2s Server 10GbE CMC Blade Enclosure Chassis
$274.99
Dell PowerEdge M620 Blade Server 2x Xeon E5-2680v2 2.8ghz 20-Cores | 128GB
$149.99
Dell PowerEdge FC430 Blade Server 2x Xeon E5-2630v4 20 Cores FX2 FX2s No RAM/HDD
$119.99
Dell Poweredge VRTX 25Bay 2.5" 2x PERC 8, 2xCMC, I/O 1GB Pass Through, 4x PS
$578.08