On Tue, Aug 24, 2010 at 11:49:56PM +0200, Lennart Poettering wrote:
> Wait, so "--all" doesn't actually show me all
targets, it shows me an
> apparently-arbitrary list of some of the possible targets?
It shows you all targets systemd knows about at that point in time.
The list of thinkable targets you could activate is more ore less
infinite, due to templating and stuff. I am pretty sure people would be
pretty annoyed if we'd dump an infinite number of targets on your screen
if you just type "systemctl".
Hmmm. I see what you are saying. And from a technical point of view, that
sounds reasonable. But here's what one part of me is hearing: wow, this new
systemd adds a whole bunch of complexity to running a machine.
That is a not a great selling point.
Is there a way to present _something_ more straightforward?
> So, most targets are actually valid for 'isolate'? What
if I go to
> bluetooth.target?
Hmm, we could add RefuseManualIsolate= to make uses like that
impossible, while still allowing "start".
/me adds this to his todo list.
Maybe the other way around -- postively list the targets which can be
manually "isolated"? (I still strongly suggest not using this term, by the
way.) Or did I take the FAQ's suggestion that this is what I want instead of
runlevels too far? My impression is that in the general state of things,
there's really only a small handful of *useful* targets for "isolate".
Well, actually it's not really reliable. You don't see what
is activated
via udev (bluetoothd for example), or via dbus, or via cron or via
anything else. It will strictly show you sysv services.
Okay, so, *THIS* is a big selling point for systemd. It knows about all that
stuff, so it can give me a nice simple list. Put things like that front and
center, and you'll have people lining up to switch.
(Minor detail that it doesn't, currently, give you that nice simple list.)
If you are looking for something 1:1 eqivalent, then just use
"systemadm"
and click on "multi-user.target" and you can click through the services it
will pull in.
That is something like a 1:500 equivalent.
Or alternatively, use something like this:
systemctl show -p "Wants" multi-user.target
Ok, cool, that's definitely a start. Can you put this in the FAQ?
Does it recurse? It'd be nice to have it in a nice list, too.
The other direction is useful as well. "When does gpm get started?" is
just "sbin/chkconfig --list gpm".
> Can I get that with systemd?
Well, we could add something that would allow you to calculate a
transaction without actually executing this. This will give you a lot
more than chkconfig ever did, as it would take into consideration what
is already running, and more than just services that are started on
boot-up, and the system state
/me adds that to his todo list.
That would be awesome. Thanks. Again, this stuff should be front-and-center.
On the todo list: it should be able to show you the change from the current
state, and the change from nothing running at all.
But don't expect this right-away, this is not completely trivial
to
implement.
Trust me, thinking that any of this is trivial is not a problem I am having.
--
Matthew Miller <mattdm(a)mattdm.org>
Senior Systems Architect -- Instructional & Research Computing Services
Harvard School of Engineering & Applied Sciences