The Debian-Live approach also provides some good opportunities. First and foremost, the very easy remastering makes it efficient to run with no persistent store quite often. For instance, upon remastering, I just start without the store, and the image I run is union-mounted with the persistence file and copied&compressed. Then I have to boot something else to copy the new squashfs image in place, but that's all that has to be done outside the system.
Boot the new image without persistence, create a new persistence file.
For further adaptations, the new persistence file can be mounted in an instance run under kvm, programs can be added and settings tweaked for an eventual new remastering.
Storing the series of squashfs-compressed images, one can always go back in this process if needed.
Dell PowerEdge R630 8SFF 2.6Ghz 20-Core 128GB Mem 2x10G+2x1G NIC 2x750W PSU
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Supermicro 4U 36 Bay Storage Server 2.2Ghz 16-C 128GB 1x1280W Rails TrueNAS ZFS
$725.06
CSE-118 Supermicro 1U GPU Server 2.6Ghz 28-C 128GB 2x Nvidia K40 GPU 2x1600W PSU
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Dell Poweredge R640 Server | 2x Xeon Gold 6132 | 128GB | H730P | 8x HDD Trays
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Intel Xeon E5-2680 v4 2.4GHz 35MB 14-Core 120W LGA2011-3 SR2N7
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Intel Xeon Gold 6140 SR3AX 2.3GHz 18-Core Processor CPU
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INTEL XEON GOLD 6148 2.40 GHz SR3B6 CPU
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HP Z4G4 Intel Xeon W2133-3.6 GHz, 256 NVME, 6TB HDD, 32GB RAM P620 NO OS
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Dell Precision T5600/t5610 Xeon E5-2670 2.6Ghz 16GB DDR3 RAM NO HDD Nvidia
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DELL PowerEdge R730 Server 2x E5-2690v3 2.6GHz =24 Cores 32GB H730 4xRJ45
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