What is an upgrade distribution system?

Question

In Apple discussion document 2465 [  https://discussions.apple.com/docs/DOC-2465  ] I found this question and answer:
Q: Are there any pitfalls to watch out for?
A: With all upgrades, backing up your data at least twice has been a given.  Hardware can fail independently of downloads and upgrades, though may happen simultaneously.  Software may be found to be incompatible that has not been tested with the new upgrade, or combination of other software that might be installed with the upgrade.  It is also strongly recommended once your backup is complete, to shut down your computer, remove all but Apple wired keyboard and mouse (notebooks remove all input devices).  Then once done, reboot, and go directly to the upgrade distribution system available.
Third party system tools, modification, and "maintenance" applications should be verified as compatible, or removed until known to be compatible.  Check with developers how to remove if it is essential to use Lion before those applications become compatible.  Most "maintenance" tools that deal with system cache, prebinding, are not really maintenance tools.  Ask on forum when are the appropriate times to use them before assuming they should be used for upgrades or otherwise.
What is an upgrade distribution system?
Thanks.

Answer 1

Well, if you happen to have several computers that run the same versions of software
and have similar need to upgrade them, essentially offline to not duplicate the costs of
bandwidth activity (and thus perhaps lose access due to overage fee or penalty) the
idea to download copies in a more traditional sense may be more difficult than with the
previous versions of OS X. With up to three Macs at similar OS X version build series,
it made sense to save all of the download compressed document or application files to
share with the other computers, to install & update them offline. And fully restore them
should the need arise, with complete copies of upgrade & updates, saved offline.
Now these require an Apple ID and other steps, the path isn't quite as clear. There may
be a path but it isn't as simple as copying a .zip file to a USB flash drive, and plug that
drive into another Mac, and drag the file to its desktop in Finder. It may be that simple
if you were to get the download without the baggage of ownership tags it may imply.
This is an area I haven't gotten into much, with only one Mac tied to an Apple ID.
The latest OS X is Mavericks 10.9.5, it is OK. I don't push it much with only 4GB RAM.
And the other computers mostly run Leopard 10.5.8. One Tiger 10.4.11. Another that
is seldom turned on, Mac OS8.6 (PowerMac 7600.) None are networked by server.
You could say I kinda made a mistake and kept a new old-stock Mini quad core server
that was ordered in December, so here it is. Although it asks on occasion for me to get
the AppleCare Plan, and extra RAM (it can use 16GB) it has two 1-TB HDDs. Sadly
both are only 5400-RPM rotational, not 7200-RPM; to supplement data transfer time.
Anyway, if you get a fair deal on a refurbished or new-old-stock i7 Mini quad core, it
may be a server model with dual hard drives. You could upgrade them & the RAM too.
And choose to not use the Server. With less RAM, now discontinued model runs OK
with the as-shipped Mavericks. Older stock was said to have Mountain Lion. Better yet
in situation where RAM and system resources are less. Yosemite likes even more...
Well, have fun with it, if possible...
Good luck & happy computing!