Hi,
On 2022/5/21 18:13, Andrew M.A. Cater wrote:
On Sat, May 21, 2022 at 01:33:02PM +0800, Zhang Boyang wrote:
Hi,
Indeed, I admit super-big-iso is a crazy idea, and a local mirror is more
useful in most cases. I think there is a few special cases that a
super-big-iso might be more useful.
1) Computers / Virtual Machines isolated from public internet or have no
network at all. It is convenient to have such an ISO to install software on
demand. A single file is much more convenient than setting up a local
mirror. It's also easy to manage or verify integrity, if frequent updates
are not needed.
If you have a computer isolated from the internet / with no network connectivitythen you
are essentially "set and forget" - because the only way to update this
is to hand carry packages in for security updates or whatever. For that, you
can use the DL-BD sized .iso - you'll need a computer that's connected to the
'Net to build it via jigdo / jigit - but you'd need a computer connected to
the internet to donwload the DVD or any other medium.
> The double-layer Blu-Ray disk sized medium is 50GB or so - so you
could write
that to a 64G USB flash disk. We - the debian images team that build and test
the images - don't routinely create all those full size images and put them in
the archive - because that would be terabytes with every point release.
They're there if you need them.
Yes, I found only two DLBD images is sufficient to contain whole debian
distribution as for now. If my idea is not accepted, I would use that :-)
Actually, setting up a local mirror is potentially almost as easy a use case
as using gigantic media files. That's exactly what many hosting companies
do in their data centres for their own use (and it's also in some of those
data centres where some of the Debian country level mirrors are located).
So a large isolated network may find it useful to have a local mirror
updated periodically.
I admit a local mirror is more suitable for large set of computers. But
for a small set of computers, for example, 1-5 computers, setting up a
local mirror might be too heavy.
2) Archival purposes. If someone (in future, for example, in 2042) want to
install a very old debian system, he/she may grab the big ISO and all he/she
need is that single file. Although it's not easy to grab the file in far
future, but I guess there is always someone crazy enough to archive all
files, isn't it? :P
See, for example, snapshot.debian.org - which is growing. See also the
cdimage.debian.org archive directory where you can find most of the .iso
files for any release. Also, keeping large files around on disk for a long
time - there's some likelihood of data corruption. I'd hate a couple of
bit flips three quarters of the way through a 6TB file, say, to mean that
the whole thing isuseless.
IMO snapshot.debian.org is centralized platform, it might be lost if
something very bad happened. For cdimage.debian.org, it's not sufficient
to archive a full debian distribution because most files are jigdos.
For bit flip corruptions, I would recommand PAR2 (Parchive 2) which can
use Reed-Solomon to create a parity archive, and that archive can be
used to fix these corruptions.
I think setting up a new variant of image is not very costly for debian
since there are already many variants, so why not give people more choices
:-)
Best Regards,
Zhang Boyang
On 2022/5/21 07:09, Andy Simpkins wrote:
On 20 May 2022 15:11:09 BST, Zhang Boyang <zhangboyang...@gmail.com> wrote:
Package: debian-cd
Hello,
I suggest debian release a new variant of ISO images, the all-in-one images.
These all-in-one image contains ALL debian packages in a single ISO image
(possibly all source packages in another all-in-one ISO image). Of course there
is no such optical media can hold such a big image, but it is useful for
virtual-machines, remotely managed servers, and archival purposes. The
theoretical size limit of an ISO9660 filesystem is about 8TB, which is
sufficient for including all debian packages.
For the name of this variant, I suggest 'everything', 'allinone', 'world',
'virt'.
p.s. This is my personal interest, and I would appreciate if you can kindly
consider my suggestion.
Best Regards,
Zhang Boyang
Sorry to put a dampener on your suggestion but why would you need that?
Why not just mirror the archive to a local disk instead?
Then you have your copy of everything and can just point a netinst at your
local mirror so you can install from there.
I think that would deliver on every use case that you would be able to use your
big ISO image and more....
Andy is absolutely right, I think.
If it helps, I'm the "other" Andy in the team along with Steve McIntyre -
and yes, I know the problems of copying large images around, have a local
mirror here and routinely build at least the single layer BD disk with
every point release.
This is a topic that comes up fairly frequently in our informal discussions
as various people have argued for various sizes of medium - someone was
asking for 128G a short while ago - practically, the impact on storage
sizes and the pain of testing each size means that we have a selection
of all possible requests.
Oh, what I thought was "building a new variant is as easy as adding a
line in build script", but it seems I was wrong. I would apologize if I
offended you. If debian image team decide to refuse my suggestion, I
would respect the decision.
It's an open question as to whether we will ever stop making media in
physical medium sizes - there's no obvious reason why an iso file needs
to fit on a DVD, for example - and then someone turns up who is still using
single layer DVDs on a regular basis. The number of people buying
burnt physical media is smaller and smaller all the time, but people still
request this from Steve and others.
With every good wish, as ever,
Andy Cater
Best Regards,
Zhang Boyang
