systemd vice SysV/LSB init systems - what next ?

[Przemek Klosowski]

On 07/19/2011 02:00 PM, Miloslav Trmač wrote:

> UNIX sysadmins know shell; so anyone can see what a shell script does,
> and how it can be configured, even if it is not documented.  Now tell
> me what /lib/systemd/systemd-quotacheck is supposed to do and how it
> is configured.

I worked with shell scripts all my life but I hate them, because they 
are fragile ahd convoluted. If something goes bad, of course they won't 
give you a global traceback, and you can't trace them by hand globally 
either---you have to figure out which script calls which script (network 
calls ifconfig calls ifup calls ...) and trace them one by one calling 
via sh -x.

> Hm.  (systemctl --all |wc -l) is 288 on my system.  That's a rather
> large number of moving parts, with no obvious way to order them or
> understand their relations.  I find it very difficult to get an
> overall picture of the system, and (systemctl dot) doesn't make it any
> better.  Perhaps there's a simple trick that I'm missing?

If there is I would like to hear it too. However, please consider that 
the overall complexity didn't change---you have 288 'services' on your 
system with SysV and systemd---it's just that systemd makes the 
relationships and dependencies explicit, whereas shell scripts covered 
up the complexity partly by serializing and partly by being lucky/having 
sorted out by trial and error the order and timing of starting those 
services.

It reminds me of symbolic math, which I learned to do on paper but had 
to relearn all over how to do using symbolic packages like Mathematica 
and Maxima, because they require precise definition of every last detail 
which was glossed over in traditional mathematical notation--I am 
talking about things like 'can we assume that this  variable is always 
greater than zero because if not the result is drastically different".