Re: Rsync and incremental updates on top of Original CDs
On Fri, 23 Feb 2001, Richard Atterer wrote:
> On Wed, Feb 21, 2001 at 02:58:48PM +0100, J.A. Bezemer wrote:
> > On Tue, 20 Feb 2001, Richard Atterer wrote:
> [snip]
> > If I understand it correctly, you first want to get all needed files
> > on some local filesystem, and assemble them to a real image later.
> > This does seem a duplication of effort, since when "jido-file
> > print-matching" knows an md5sum of some file, it also knows its
> > place in the CD image and can easily copy it there directly
> > (assuming jido-file is not a shell script ;-), as in:
> >
> > <insert and mount CD>
> > find /cdrom -type f \
> > | jido-file copy-matching \
> > --files-from=- --template=potato.iso.template --output=potato.iso \
> > --already-done=potato.iso.already-done
> >
> > where already-done would contain md5sums of files that were already
> > copied to the .iso earlier (something like your --cache).
>
> True, something like that would be useful. I think you could actually
> get away with appending to potato.iso the information regarding which
> files have already been copied into the image, and remove that
> "trailer" when you're finally done. (It might be wise to use a name
> "potato.iso.tmp" and only rename it to "potato.iso" when finished.)
Nice idea, but AFAIK shortening a file is impossible (at least C doesn't seem
to have a function for it). And besides, it would be very helpful if the
"already-done" file was just plain ascii text (md5sum with filename as
comment?) that could be changable easily, for example to force a file to be
downloaded again (for whatever reason).
The .tmp name for an unfinished image surely would make things a bit clearer
to unexperienced users. I can imagine some "jido-finalcheck" tool that checks
the md5sum (gotten from...where? --md5sumfile=MD5SUMS ? image=okay if matches
any listed md5sum?) and if okay renames the .tmp to .iso.
> > Followed by either
> >
> [ a) jido-file print-missing, then fetch files that are output and
> jido-file copy-matching]
> [ b) jido-net get-and-copy-missing
> which would do the getting and copying at once.]
>
> I prefer a), because I want to draw a line between the jido-file tool,
> whose main purpose it is to /generate/ the .template files (but which
> is also capable of reassembling images as an add-on feature), and
> jido, the "client program" with GUI, automatic mirror selection etc.,
> which can only reassemble images from template+files+downloads, and
> nothing else.
Very well -- but don't be surprised if some guy who likes b) better suddenly
mails you a "jido-net" implementation ;-)
> > > Would it be OK for you to update the kit once
> > > jido-file is in a working state?
> >
> > You mean to create a modified make-pseudo-image to get missing files
> > to some local dir? That shouldn't be too hard for me ;-)
>
> Yep. It is easy to add IMHO too, but easier for you because apparently
> you are in a position to do proper tests, with a local Debian mirror
> present.
Actually, now that you're an Official Developer, you should have access to a
lot of Debian machines; I suppose a few have a local mirror and enough disk
space to test things. And if not, we can probably arrange an account on
cdimage.d.o (full local mirror, all official CDs and 7GB free in /home ;-).
(Not that I don't want to help; it's just that it might be easier to do/test
things yourself. Unless you're using some terribly expensive slow modem
connection of course...)
Regards,
Anne Bezemer
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