Thank you for the replies. My main takeaway is do the
major LTS upgrades "rapidly-sequentially": for example,
make a one week "pit stop" at 24.04 while upgrading
from 22.04 to 26.04 .
Practically speaking, re-learning Linux system details
takes a few weeks for me, even with copious notes from
"last time". My profession is hardware engineering,
the details are physics and chemistry (and lately,
orbital mechanics). Relearning Linux OS details for
maintenance is distracting. A lot of those details
are encoded in home-made simulation code connected to
math libraries - I must transition that work too.
The VM idea sounds be a good way to encapsulate some of
that custom work - along with notes about how I did it
and the software I used to do it and where I found the
software. The downside of VM is that container systems
themselves go in and out of fashion; before I do that,
I hope to learn which virtualization is most likely to
endure ... for decades.
Being 68 years old, "decades" seems optimistic ... but
I just signed a birthday card for my 105 year old
father-in-law, who led building repair teams as recently
as ten years ago. Some of my own distributed team is
in their 20's, so I probably won't be able to answer
questions ("what the HELL was Keith thinking???")
50 years from now.
Simulation plus VM - hopefully the VM overhead added to
a kludgy numerical simulation spread out across multiple
processor cores won't slow it down by more than a factor
of two. I ponder migrating some of those nested C loops
graphics coprocessors, but that seems incompatible with
abstract virtualization.
One of the advantages of Ubuntu/Debian over CentOS/RH
is that there are fewer copyright/ownership hassles
for the proliferation of third party repositories for
source archives. And there are enough renegade geeks
maintaining oddball variants that I can probably find
archives compatible with the in-the-future-unfashionable
variants that I've chosen.
So -- thanks again!
Keith
P.S. "Clock of the long now" ... how do you format a
maintenance manual so that it is readable 10,000 years
from now?
--
Keith Lofstrom kei...@keithl.com
