[CentOS] Disappearing Network Manager config scripts

[Lamar Owen]

On 04/29/2014 02:42 PM, Steve Clark wrote:
> This may be fine for users that don't know what they are doing or 
> don't have a stable networking environment, but I have found for me it 
> causes nothing but heartache. 

Steve, first, if this comes off as a rant, that's not my intention, and 
it's not directed to you personally.

My experience?  There is no such thing as a 100% stable networking 
environment.  Systems like Tandem's NonStop take that a step further, 
and realize that there's no such thing as a 100% stable CPU, either.

This whole discussion reminds me of the SELinux discussions, and the 
oft-quoted advice to just disable it, it just gets in the way of The Way 
I'm Used To Doing Things (TM).

> The first thing I do is disable it. The sad part is that it makes us 
> not understand what is really happening with our systems and when 
> something doesn't work we have no idea where to look.

NetworkManager is well-documented.  You just have to read the docs and 
be willing to try something new.  It also logs to /var/log/messages in 
plain text, too.  There are more pieces, yes, to trace through.  But, 
unless you install the Desktop group or the anaconda package on your 
server you won't get NetworkManager on it. If you install the Desktop 
package, there's a bit of an assumption that you want a Desktop, no?

> I have been using UNIX/BSD/Linux since the mid eighties and hate where 
> things appear to be going - looking more and more like Windows. my $.02 

Looking like Windows is not a capital crime.  (No, I am not a Windows 
freak; I've used *nix of various types probably as long as you have, and 
I haven't used any Windows as my primary desktop of choice since Windows 
95 was a pup, and have never used a Windows Server as my primary server 
of choice.)

NetworkManager's goal is extremely simple, and is in the README. It's 
simply: "NetworkManager attempts to keep an active network connection 
available at all times."  Networks are unreliable. Period.  That's why 
we have BGP and OSPF and all the other interior and exterior gateway 
protocols, because network links are 'best-effort' services; QoS depends 
upon the expectation of unreliability, in fact, since the only way to 
guarantee any packet a timeslot in a full pipe is to throw a different 
packet out the door.  See the absolutely delightful video 'Warriors of 
the .Net' (www.warriorsofthe.net and elsewhere).  We bond interfaces 
because one could go down, right?  (This is one area where NM is weak, 
incidentally).

I cannot foresee every failure in any manual configuration.  We have 
dynamic routing protocols for a reason, since nobody can foresee how to 
weight every possible static route.

Back in the late 1800's people who had used tillers to steer their 
horseless carriages probably though the same thing about this new fancy 
gizmo called a steering wheel.  And automatic transmissions? Heresy!

Much of what I learned with Xenix on the Tandy 6000,  Convergent Unix 
System V Rel 2 on the AT&T 3B1, Apollo DomainOS (using the 4.3BSD 
'personality' for the most part), SunOS and later Solaris on Sun3 and 
SPARC hardware, and older Linux on PC and non-PC hardware still applies; 
but things move on as requirements change.  (At least I can still have 
my vi!  I HAVE used vi since the 80's, and it is still the same quirky 
beast it always was, even in Xenix V7 on the T6K.).

But the GUI on the 3B1?  And those 'pads' on DomainOS?  Not portable, 
and fallen by the wayside.

Older does not mean better, and many times newer things have to be tried 
out first to see if they are, or aren't, better.  Systemd is one of 
these things, and it will be interesting to see how that all plays out 
over the next few years.