Ewald Peters wrote:

> i don't know right now, but if it works i had the idea of
> burning cds for a printer server, a
> internet-surving-only-workstation with X, a firewall, a
> webcam-server - whatever and everything without the need of a
> harddisk everything OBSD 3.2 on a intel 486 or Pentium 166 or
^^^^^^^^

Hmm, I implicitly assumed you were using OBSD 3.3, the source of
your problems _might_ be just that. What if you tried doing your
livecd system with 3.3 instead of 3.2?

Do you have a spare HD which you could plug into the computer you
will use with the livecd? If so, you could install fresh OBSD on
that HD, configure it, add packages etc. and THEN you would make
the modifications to /etc/rc, /etc/fstab et.al. After this you
would burn the cd from the HD and remove the HD from the
computer. This might be the easiest way to be sure that your
problems are not related to the OBSD being misconfigured but
truly related to booting from cd.

> cd-boot-capability of course. with 16, 32, 128 MB Ram

I would recommend as much RAM as possible and pushing the kernel
option BUFCACHEPERCENT to as big as possible so you would the get
the biggest benefit of cache as cdrom access is slooooow... But
this you already knew, I guess.

> ok i got this right now, but what about /usr and /root which is
> nessessary for X because the binaries and config files and the
> 'X-link' is in /usr/X11R6 and in /root there is .Xauthority.

What do you need /root for? You are not logging into the computer
as root, are you? Big Boys Say that you should avoid logging in
as root but use instead sudo and su from a normal, unpriviledged,
user account. See manual pages for sudo and su.

> first i mount fstab like you (is 'swap /tmp mfs
> rw,nodev,noexec,nosuid,noatime,-s=262144 0 0' really right? X
> needs this dir to create several files ...)

Is there something wrong with it? /tmp is mounted on a memory
filesystem which is read-write so e.g. X can write into it.

> secondly i mount_union the rest of the CD in /tmp like
> http://www.blackant.net/other/docs/h...om-openbsd.php
>
> i think this works now (only the mounting)

I tried that but I had some weird problems, like mysterious
extra directories suddenly appearing in /usr.

> so you think /root and /bin /sbin /usr can stay read only? is
> this really the case? what does 'mount' say on your system?

In my opinion, yes with the possible exception of /root. Honestly
speaking I forgot all about that directory , but so far my
system works quite fine with /root mounted read-only.

output of mount:

/dev/cd0a on / type cd9660 (local, noatime, read-only)
mfs:27877 on /dev type mfs (asynchronous, local, noatime, \
union, size=12000 512-blocks)
mfs:14294 on /tmp type mfs (asynchronous, local, noatime, \
nodev, noexec, nosuid, size=262144 512-blocks)
mfs:26743 on /var type mfs (asynchronous, local, noatime, \
size=262144 512-blocks)
mfs:16007 on /etc type mfs (asynchronous, local, noatime, \
size=131072 512-blocks)
mfs:1247 on /home type mfs (asynchronous, local, noatime, \
size=262144 512-blocks)

[long lines wrapped to fit into screen]

> ok, now i know that there is a miniroot filesystem included
> into the kernel image which is not only the kernel itself
> inside this miniroot filesystem there are such important things
> like /sbin/init and this init seem to mount / as it is
> discribed in the kernel option file, independently of
> /etc/fstab. As soon / is there it reads /etc/rc devices from
> /dev aso.

Correct, this is the way I've have understood the boot process to
go.

> So the process to build the filesystem for the live-CD can be
> either mount_mfs mount_union or whatever as long it works. But
> this is the dificult thing: to make the applications believe,
> that they live on the harddisk, where they have been before.

Why should well-behaving *nix applications care if they are on a
cd or a hd? They see the same file structure as previously, only
now parts of it is on a read-only partition. With Windoze your
problem is true, at least to some extent.


Have fun with your hd-less workstations and do let us know of
your experiences when/if you succeed with your attempts.


Have a nice day now,

sami