Re: Sysstemd question

2022-11-13 Thread David Wright
On Sat 12 Nov 2022 at 18:12:28 (-0500), pa...@quillandmouse.com wrote:
> On Sat, 12 Nov 2022 11:04:39 -0500 Greg Wooledge wrote:
> > On Sat, Nov 12, 2022 at 10:41:15AM -0500, pa...@quillandmouse.com
> > wrote:
> > > Folks:
> > > 
> > > I've been reading up on systemd, both from Red Hat's documentation,
> > > Debian's and the man files. One thing I haven't been able to
> > > explain is why systemd has config files in /etc, /lib, /run, and
> > > /usr/lib.
> > 
> > /lib and /usr/lib are the same thing, or will be the same thing in a
> > future release.  Don't worry about that.
> > 
> > /run is transient.  It's an in-memory file system, created and
> > populated at boot time, or by running programs.  It's not a place for
> > configuration.
> > 
> > So really you're looking at /etc vs. /usr/lib.
> > 
> > /usr/lib contains the defaults created by the Debian maintainers or
> > the upstream authors.  When you install a new package that has a
> > systemd unit file, that's where it'll go.
> > 
> > /etc contains the overrides and configuration elements that are unique
> > to your system.  If a service is masked or disabled, it'll be done
> > here. If you install a locally built service, and write a systemd
> > unit for it, this is where you'll put it.  If you override part or
> > all of a package's unit file, you do it here.
> > 
> 
> Thanks for this excellent explanation. I wish the folks who write docs
> would try to explain things in English instead of geek-ese. I'm a
> programmer, and I try to keep this in mind whenever I write docs. That
> said, though, the Red Hat docs for systemd are pretty good.

You might try reading the similar explanations that sometimes appear
at the start of a few systemd manpages from section 5; for example,
systemd.dnssd, systemd.link, systemd.netdev and systemd.network are
the ones installed on this system of mine.

It's also touched on in http://0pointer.de/blog/projects/three-levels-of-off
which is part of a series of blogs on systemd. Perhaps peruse
https://www.freedesktop.org/wiki/Software/systemd/ for a large number
of systemd documents and background.

Cheers,
David.



Re: Sysstemd question

2022-11-12 Thread Amn

I second that opinion!!!

On 2022-11-12 6:12 p.m., pa...@quillandmouse.com wrote:

On Sat, 12 Nov 2022 11:04:39 -0500
Greg Wooledge  wrote:


On Sat, Nov 12, 2022 at 10:41:15AM -0500, pa...@quillandmouse.com
wrote:

Folks:

I've been reading up on systemd, both from Red Hat's documentation,
Debian's and the man files. One thing I haven't been able to
explain is why systemd has config files in /etc, /lib, /run, and
/usr/lib.

/lib and /usr/lib are the same thing, or will be the same thing in a
future release.  Don't worry about that.

/run is transient.  It's an in-memory file system, created and
populated at boot time, or by running programs.  It's not a place for
configuration.

So really you're looking at /etc vs. /usr/lib.

/usr/lib contains the defaults created by the Debian maintainers or
the upstream authors.  When you install a new package that has a
systemd unit file, that's where it'll go.

/etc contains the overrides and configuration elements that are unique
to your system.  If a service is masked or disabled, it'll be done
here. If you install a locally built service, and write a systemd
unit for it, this is where you'll put it.  If you override part or
all of a package's unit file, you do it here.


Thanks for this excellent explanation. I wish the folks who write docs
would try to explain things in English instead of geek-ese. I'm a
programmer, and I try to keep this in mind whenever I write docs. That
said, though, the Red Hat docs for systemd are pretty good.

Paul





Re: Sysstemd question

2022-11-12 Thread paulf
On Sat, 12 Nov 2022 11:04:39 -0500
Greg Wooledge  wrote:

> On Sat, Nov 12, 2022 at 10:41:15AM -0500, pa...@quillandmouse.com
> wrote:
> > Folks:
> > 
> > I've been reading up on systemd, both from Red Hat's documentation,
> > Debian's and the man files. One thing I haven't been able to
> > explain is why systemd has config files in /etc, /lib, /run, and
> > /usr/lib.
> 
> /lib and /usr/lib are the same thing, or will be the same thing in a
> future release.  Don't worry about that.
> 
> /run is transient.  It's an in-memory file system, created and
> populated at boot time, or by running programs.  It's not a place for
> configuration.
> 
> So really you're looking at /etc vs. /usr/lib.
> 
> /usr/lib contains the defaults created by the Debian maintainers or
> the upstream authors.  When you install a new package that has a
> systemd unit file, that's where it'll go.
> 
> /etc contains the overrides and configuration elements that are unique
> to your system.  If a service is masked or disabled, it'll be done
> here. If you install a locally built service, and write a systemd
> unit for it, this is where you'll put it.  If you override part or
> all of a package's unit file, you do it here.
> 

Thanks for this excellent explanation. I wish the folks who write docs
would try to explain things in English instead of geek-ese. I'm a
programmer, and I try to keep this in mind whenever I write docs. That
said, though, the Red Hat docs for systemd are pretty good.

Paul

-- 
Paul M. Foster
Personal Blog: http://noferblatz.com
Company Site: http://quillandmouse.com
Software Projects: https://gitlab.com/paulmfoster



Re: Sysstemd question

2022-11-12 Thread Greg Wooledge
On Sat, Nov 12, 2022 at 10:41:15AM -0500, pa...@quillandmouse.com wrote:
> Folks:
> 
> I've been reading up on systemd, both from Red Hat's documentation,
> Debian's and the man files. One thing I haven't been able to explain is
> why systemd has config files in /etc, /lib, /run, and /usr/lib.

/lib and /usr/lib are the same thing, or will be the same thing in a
future release.  Don't worry about that.

/run is transient.  It's an in-memory file system, created and populated
at boot time, or by running programs.  It's not a place for configuration.

So really you're looking at /etc vs. /usr/lib.

/usr/lib contains the defaults created by the Debian maintainers or the
upstream authors.  When you install a new package that has a systemd
unit file, that's where it'll go.

/etc contains the overrides and configuration elements that are unique
to your system.  If a service is masked or disabled, it'll be done here.
If you install a locally built service, and write a systemd unit for it,
this is where you'll put it.  If you override part or all of a package's
unit file, you do it here.



Sysstemd question

2022-11-12 Thread paulf
Folks:

I've been reading up on systemd, both from Red Hat's documentation,
Debian's and the man files. One thing I haven't been able to explain is
why systemd has config files in /etc, /lib, /run, and /usr/lib.
I also can't find in what order systemd scans these directories. Also,
why it's necessary for there to be symlinks in /etc/systemd/system to
files in /lib/systemd/system. These questions may be a bit too esoteric,
but if anyone could explain, or point me to documentation, I'd
appreciate it.

Paul

-- 
Paul M. Foster
Personal Blog: http://noferblatz.com
Company Site: http://quillandmouse.com
Software Projects: https://gitlab.com/paulmfoster