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helloSystem / ISO

helloSystem Live and installation ISO
https://github.com/helloSystem/
BSD 3-Clause "New" or "Revised" License
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Consider bwf write filter #409

Closed probonopd closed 1 year ago

probonopd commented 1 year ago

We have been struggling at producing a reliable Live system that appears to be fully read-write while being booted from read-only media such as ISO.

bwf, the Beckhoff Write Filter, is described as follows:

As is familiar from the Windows operating system, TwinCAT/BSD provides a write filter. This protects the system against persistent changes. With the write filter activated, the system is in a previously defined state following a restart.

https://infosys.beckhoff.com/english.php?content=../content/1033/twincat_bsd/7873538059.html describes how to use it.

It can be downloaded from https://tcbsd.beckhoff.com/TCBSD/13/stable/packages/All/ (by the way, unlike FreeBSD, this package repository allows directory listing and has a neat https://tcbsd.beckhoff.com/TCBSD/13/stable/packages/packagesite.html page)

The package names "SLA4BSP" as the license ("This package has a single license: SLA4BSP (Software License Agreement for Beckhoff Software Products)"). Is it open source? I can't seem to find it on https://github.com/Beckhoff.

It would remain to be tested whether bwf can be used to get a reliable Live system from read-only media such as ISO.

probonopd commented 1 year ago

Looking at usr/local/bin/bwfctl it seems like this is "just" elaborate zfs trickery, and we already found out that zfs is apparently not capable of making a read-only device (like an ISO) appear read-write.