[CentOS] OT: systemd Poll - So Long, and Thanks for All the fish.

Mon Apr 24 15:52:02 UTC 2017
Warren Young <warren at etr-usa.com>

On Apr 24, 2017, at 7:53 AM, Lamar Owen <lowen at pari.edu> wrote:
> James' point isn't the hardware cost, it's the people cost for retraining.

Unless you’ve hired monkeys so that you must train them to do their tasks by rote, that is a soft cost, not a hard cost.  If you’ve hired competent IT staff, they will indeed need some time to work out the differences, but they will do that on their own if only given that time.

Note also that Byrne’s solution was to move to an entirely different OS, but we don’t hear about the “retraining cost” involved with that.  Surely it was a larger jump from C6 or C7 to FreeBSD 10 than from C6 to C7?

He also seems to be sweeping aside the fact that FreeBSD major releases generally stay in support for about half the span of RHEL and its derivatives.  If he wants to stay on a supported OS the whole time that C7 remains in support, he’s probably looking at 2 major OS version upgrades.

It’ll be interesting to see how much change FreeBSD gets in the next 7 years.

> In many ways the Fedora treadmill is easier, being that there are many more smaller jumps than the huge leap from C6 to C7.

That depends on the organization and its goals.

If you have a true IT staff that exists just to keep servers up to date and working properly, then yes, you’re right, smaller upgrades every 3-6 months are often easier to handle than trying to choke down 2-10 years of changes all at once, depending on the LTS release strategy and how many major upgrades you skip.

If you’re trying to treat the OS as a base atop which you do something else, and you just need something that will keep working for 2-10 years despite being continually patched, then choking that big ball of changes down every 2-10 years might be preferable.

My main point is that if you’re going to take the second path, don’t cry about how much change there is to choke down when you’re finally forced to move forward.  You choose to put off dealing with it for many years; the chickens have come back home to roost, so there will of course be a lot of work to do.

> ...dual-socket Opteron LS20 blades (10+ years old)...CentOS 7, once installed, works great...

That doesn’t really contradict my point.

First, I said “most” hardware, but you’ve gone and cherry-picked uncommonly durable hardware here; you’re probably out in +3 sigma territory.  A lot of commodity PC-grade SOHO “server” hardware won’t even last the 3 years between major CentOS upgrades before dying of something.  There was a period where I’d budget 1-2 years for a Netgear switch, for example.  (They appear to be lasting longer now.)

Second, the application of my quoted opinion to your situation is that you should run that hardware with CentOS 7 through the EOL of the hardware or software, whichever comes first.  That is, I’m advising the change-adverse members of the audience to opt into the second group above, taking OS changes in big lumps when it’s time to move to new hardware anyway.