Linux command comparison

Hans Fugal hans at fugal.net
Fri Dec 8 19:32:36 MST 2006


Runlevels are a nice idea that I've not found much use for personally
(except for single user mode, if you count that). In any case, there's
nothing about runlevels that requires sysv init, it could just as easily
be part of $newfangled_init, although it often isn't (as a design
decision).

Personally I think dependencies and monitoring trumps runlevels any day
of the week. My life has been so much better since I let the computer
worry about whether bind had crashed recently. My toenails even grow
straighter.

On Fri,  8 Dec 2006 at 09:48 -0700, Michael Torrie wrote:
> On Fri, 2006-12-08 at 06:56 -0700, Hans Fugal wrote:
> > I heartily agree, although it bears mentioning that some distros are
> > making the long-overdue migration away from System V init schemes (the
> > symlinks in /etc/rc.d or similar places) to something better. e.g.
> > Ubunutu is using upstart, which looks very cool, and Debian has optional
> > support for upstart and other systems like runit.
> 
> For a desktop distro this is probably a good idea, but for servers,
> nothing beats System V in my opinion.  Having well-defined custom
> runlevels (something most of us probably should do but don't) allows for
> much better system administration.  For example, if your server
> applications are layered, you can use runlevels to add layers in a
> controlled fashion.  Runlevel 5 could be everything up full, and
> runlevel 4 could be everything but the web interface, runlevel 3 could
> be just the sql server running, and runlevel 2 could be standard
> multi-user, network, but the apps are shut down for maintenance.  
> 
> Having messed with Tiger's new LaunchDaemon, I can see some definitely
> benefits to it over the older pseudo-rc system.  But it seems to not
> have any real concept of runlevels, although there Mac does support a
> single-user mode, so I don't know how it fits in.
> 
> Michael
> 
> > 
> > In any case, get under the hood. A good excercise is to manually walk
> > through everything that happens at boot until your gui or login prompt
> > pops up. It will take some googling and asking, bu it will be
> > enlightening!
> 
> 
> > 
> > On Fri,  8 Dec 2006 at 00:42 -0700, Alex Esplin wrote:
> > > On 12/8/06, Doran Barton <fozz at iodynamics.com> wrote:
> > > >Even though tools exist on different distributions (chkconfig for
> > > >RH/Mandriva, update-rc.d on Debian(isms), yast on SUSE), they all do mostly
> > > >the same dang thing: maintain symbolic links between files in /etc/init.d 
> > > >(or
> > > >/etc/rc.d/init.d) and the run level directories init scripts process for 
> > > >the
> > > >respective run level.
> > > >
> > > >If you learn about the fundamental activity these tools are doing, the 
> > > >tools
> > > >themselves are just convenience. Knowing what's going on behind the scenes,
> > > >you can pretty much manage anything on any of the distributions.
> > > 
> > > I would tend to agree fairly strongly on this.  Not that I am making
> > > any claims to knowing anything, but after using Gentoo for a while, I
> > > know a heck of a lot more about other distributions than I did before.
> > > So pick your favorite distro and do some digging into how it handles
> > > all of that stuff, and most of that knowledge will carry over.
> > > 
> > > -- 
> > > Alex Esplin
> > > 
> > > /*
> > > PLUG: http://plug.org, #utah on irc.freenode.net
> > > Unsubscribe: http://plug.org/mailman/options/plug
> > > Don't fear the penguin.
> > > */
> > > 
> > 
> > /*
> > PLUG: http://plug.org, #utah on irc.freenode.net
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> > */
> 
> 
> /*
> PLUG: http://plug.org, #utah on irc.freenode.net
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> 

-- 
Hans Fugal ; http://hans.fugal.net
 
There's nothing remarkable about it. All one has to do is hit the 
right keys at the right time and the instrument plays itself.
    -- Johann Sebastian Bach



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