>> 1. How is the LiveCD file system constructed/built? I've read a variety >> of articles and it seems that it is close to the UnionFS (rom+ram >> "partitions"), but I am not sure that is used with the new versions of >> Linux. I see there are multiple loop mounts on the system, but can't >> figure out what they are. >> > > It is originally written into an ext4 image. That image is then compacted > and then written to a squashfs file system. > I am aware of all that - squashfs.img is constructed (which encapsulates the real ext3/4 partition in a separate file - ext4.img I think it was called), but what I was after is how is this actually mounted on the live system so that it is "read-write"? From what I can see there are multiple loop partitions used (in conjunction with dm), but this is as far as my knowledge goes, unfortunately.
>> 2. My understanding is that all files that are modified in the "live" >> image are stored "separately" on a "ram partition". If that is indeed >> the case, can I look at what has been "modified" during the live >> session? This is easily visible and implemented in UnionFS by a simple >> "ls" on the ram (i.e. the read-write) part of the UnionFS, but I am not >> sure how this is organised on the LiveCD system. >> > > A dm overlay is used. This can either be ram or separate overlay spaces > for /home and/or /. I don't have /home, so just /. Could you tell me how is it actually done at boot up and how is it made "read-write"? I presume there must be some sort of space where this information is written - I assume it is the ram, but I am not 100% sure. > I don't think this makes it easy to look at just what's > changed (in terms of efficiency, not commands). You can use find to find > files with a recent ctime, but you'd need to check every file. > I know that, but, as you rightly pointed out, I have to trash the whole / partition and even then this won't be a complete solution as I also need to know the time when the system booted up - it is all a bit clumsy, there must be a better solution to this. -- livecd mailing list [email protected] https://admin.fedoraproject.org/mailman/listinfo/livecd
