[Pkg-ltsp-devel] Bug#509640: ltsp-server: confusing out of the box experience

[Ross Boylan]

On Wed, 2008-12-24 at 10:55 -0800, Vagrant Cascadian wrote:
> On Tue, Dec 23, 2008 at 05:51:40PM -0800, Ross Boylan wrote:
> > I just installed this package, and there were a lot of things that seemed odd
> > or confusing.
> 
> thanks for your report!
>  
> > The reference to /opt in the package installation and man
> > ltsp-build-client seemed odd, because Debian doesn't use that (not
> > sure abou FHS).  I thought the defaults when I ran it would be
> > different, but they weren't.
> 
> arguably, according to the FHS ltsp should probably be installed in /srv,
> though when LTSP was first developed, /srv didn't even exist. all other LTSP
> implementations use /opt/ltsp, so we decided to stick with it for Debian.
One practical problem with /opt is that, since it didn't exit, it ended
up on my small root partition, which then filled.  I suspect that may be
pretty typical, at least for those who don't just use one giant
partition for everything.

My suspicion is there's some reason Debian packages don't seem to
use /opt, but I'm no authority.
....
> > man ltsp-build-client uncertainties:
> > Does this need to be run as root? (yes)
> 
> > Do "mirrors," "packages", and "distribution" refer to the usual Debian
> > things of that name, or is it some upstream concept? (apparently
> > Debian)
> 
> do you have some proposed text you would like to see added to the man page for
> the above two items?
> 
For the first, "This command must be run as root." (if that's true).
For the others, maybe just insert "Debian" before the word, and give an
example.  For "package", maybe use "package name" to clarify that it's
"ltsp-server" not "ltsp-server_5.1.10-2_all.deb".

> > If I change base do I need to tweak the clients, or is that automatic?
> 
> the client doesn't need to know anything about the base location, however, some
> of the server tools (ltsp-update-sshkeys, ltsp-update-kernels) may need to be
> explicitly told to use the alternate locations. using an alternate base
> location is not well tested, and there are likely bugs.
> 
> > To try to summarize what I think would help:
> > 1. build an /etc/ltsp directory and populate it with sample config
> > files, if appropriate (that is, if packages are supposed to create
> > their /etc/ directories).
> 
> i would consider doing such with /usr/share/doc/ltsp-server/examples, but i'm
> not going to populate /etc/ with configuration files unless they're actually
> needed to function properly, as the defaults work without them.
By samples, I meant files with comments, including commented out
configuration statements.  I didn't mean "live" statements that might
not be appropriate.  This could be in place of or in addition to a
fuller man page (though I think the man page is always a good idea,
since people can delete the file with comments).
> 
> > 2. Change the default chroot to something more Debianny,
> > e.g. /var/ltsp if appropriate (policy consistent).
> 
> again, i think /opt is not inappropriate according to FHS, even if /srv is more
> appropriate.  but there is a huge amount of and cross-distro consistancy and
> documentation lost by switching that location.
> 
> > 3. Provide more of an overview.
> 
> where do you think an overview belongs? 
In /usr/share/doc/.
> is http://wiki.debian.org/LTSP/Howto
> insufficient?
That was helpful when I found it.  It would also be helpful if it
included a description of the different packages and how they fit
together, e.g., the roles of the different servers (dhcp, tftp, nbd,
nfs, inet).

More info on the construction of the chroot would be good too.

One step further back, the basic setup this is aiming for would be
useful.  I'm slowly realizing it's aiming for something different from
what I was intending.  I wanted to have the remote computer act as an X
terminal that had an X server and little else: it would get the login
screen from kdm running on my server.  So after login it would be
running on my server (except for the X server itself).  I think ltsp is
setting up something different, in which the X terminal is running
inside the chroot + some writable space served by nbd.
> 
> > 4. Provide more details in the man pages, including the format of the
> > configuration files (I found ltsp.conf configuration on the web, but
> > nothing for the builder).
> 
> they're all NAME=value pairs, though a brief overview in the manpages
> would be a good idea, 
also, do the values need to be quoted? are there comments?
> it would be hard to write in a distro-agnostic
> way, 
Do you mean the values for NAME (e.g., BASE) are distro dependent, or
the values on the right of the assignment are distro dependent?
> as the relevent values would be totally different. so i might just
> stick with example configuration files.
I thought ltsp was intended to be customized for each distro.
> 
> > 5. Use ltsp consistently for file names (or lts).
> 
> lts.conf is kept as is for historical consistancy, everything else uses "ltsp".
> 
> > There's probably a lot I'm misunderstanding, but it would be nice if
> > it were easier to understand :)
> 
> it always is, yes. :)
>  
> > I'm also a little puzzled that both nbd-server and a tftpd server are
> > necessary (and an nfs server), though I'm willing to take it on faith.
> 
> tftp is needed to boot with PXE, nbd-server is needed to provide network swap,
> and nfs-kernel-server is used for the root filesystem.
> 
> i hope these explanations help. i'll try and address some of the issues, though
> probably post-lenny, as we're in freeze.
Terrific.

By the way, after doing everything, the client hung up after contacting
the tftp server.  The tftp server appears to be responsive from other
clients on the network, so I'm not sure if this is a result of something
else being off (I've done nothing to setup nbd, and there was a warning
message about its not having a config file on install), or if the PXE
boot ROM program I'm using (from http://rom-o-matic.net/) isn't working.
The harware rom doesn't support PXE, nor can I get it to boot from a CD.

Merry Christmas!
Ross