Re: What is this "update" ISO image?

[Steve McIntyre <steve@einval.com>]

Ken Teague wrote:
>What is this "update" ISO image I see in the cd-image archives?  For
>example, on http://mirrors.kernel.org/debian-cd/4.0_r6/i386/iso-dvd/ I
>see debian-update-4.0r6-i386-DVD-1.iso.  What are these update ISO
>images used for?  Thanks in advance.

http://www.debian.org/CD/faq/#update-cd :

   Update CDs are CDs which contain all the packages that changed
   between the rev0 and a later revN release of the current stable
   distribution. For example, if you already have the full set of
   3.0rev0 CDs, you can use the "update-3.0rev2" CD to turn this
   3.0rev0 set into a 3.0rev2 set.

   This type of CD is intended for vendors having large amounts of
   pressed rev0 CDs (which makes them cheaper than individually burned
   CDs). If you order CDs from such a vendor, it is possible that you
   receive CDs for a slightly older revision, plus an update CD for
   the latest revision. This is a perfectly acceptable way of
   distributing Debian on CD.

   Of course, this type of CD can also be useful to you as an end
   user; instead of creating the full set of CDs for each new revision
   of a release, you only need to download and burn one or two update
   CDs for your architecture.

   You only need to download either the update CD or the normal CDs,
   not both!

   Now, what if for some reason you do not want to download the update
   CD even though you already have the full set of CDs for the
   previous revision? In this case, you should consider using jigdo's
   "update" feature: jigdo can read the contents of the old CDs,
   download only those files that have changed for the new CDs, and
   create the full set of new CDs. Still, it will have done this by
   downloading only about the same amount of data as for an update CD.

-- 
Steve McIntyre, Cambridge, UK.                                steve@einval.com
Who needs computer imagery when you've got Brian Blessed?