Steffen?

initrd -> hannes  

What are the contents of /etc/sysconfig/kernel:INITRD_MODULES?

jfs should be listed there. If it isn't, it won't be included in the initrd.

When the system boots the first time, INITRD_MODULES contains: "piix processor
thermal fan" - as prepared by the installer.
The important question here is - why isn't "jfs" in the list?  I would expect
the installer to understand that the root filesystem is JFS, and that it
therefore needs to include jfs in the initrd.

That's what I would expect, too.
Reassinging to the YAST folks.

Thomas, Arvin, it's partitioner task to tell Initrd.ycp to include the 
module...  

Please attach y2log files.

JFS is not support as root filesystem.

I know the installer no longer supports JFS, but that JFS is not supported as
root filesystem is news to me.  When was that announced? 
Besides, how come the installation on to a JFS root works just fine, if there's
no support for a JFS root filesystem? 

If the installer does not support JFS at all, of course it also does not
support it as root fs. 
No idea if and when that was announced. I doubt is was announced at all.

Ah, but the installer _does_ have some support for JFS.  The point I was trying
to make is - the installer has no problem _installing_ on to a JFS root, it just
doesn't support _creating_ JFS filesystems.  And subsequently, the system does
not currently support booting off JFS.  

What I'd like to know is - _why_ can't this be supported?  It really is just a
very simple matter of adding 4 characters to the INITRD_MODULES line in
/etc/sysconfig/kernel. 

The only problem that that I'm aware of that would explain why jfs is not
supported on the root is bug 67328, which unfortunately was not fixed in time to
make 9.3.  Is there any reason not to support jfs on / in subsequent releases?

Let me clarify:

* An update from an older release that uses JFS partitions should work
* A new installation with partitioning of JFS is not supported by YaST
* A new installation with reusing an existing JFS partition might work
  but this is not a supported method of installation at all.


Each and every filesystem needs tool support, implementation in YaST, testing,
bug fixing etc.  In the past while we supported JFS, we noticed that we had no
real external JFS testers and users and therefore decided that the engineering,
QA and fixing effort is not worth it for SUSE Linux distributions.

For future products, we consider adding an "expert" mode that allows
installation of additional filesystems but comes with a big warning that these
filesystems are unsupported and might not work at all (and will not be a blocker
or critical bug).  Would that help?

Thanks for the explanation Andreas.

With respect the your item #3, yes, this works just fine - until the system
needs to boot.  

About JFS support in SuSE Linuxes - SLES has full JFS support.  Surely the
engineering, QA and fixing effort could be more or less borrowed there? 
Obviously it's not my job to tell SuSE how to organise their staff, but it seems
a possibility.

Finally, I can't help thinking that when you allow installation onto a JFS root,
it would be sensible to also allow booting from it.  Note, I say _allow_, not
_support_.  All I'm concerned about is to skip the cumbersome step of booting up
a rescue system to fix the initrd before booting the first time.  
You _could_ just add jfs to the INITRD_MODULES - as you support JFS filesystems
as such, loading the jfs module at boot-time won't make much of a difference, I
submit. 

We could borrow from SLES when we do a SLES release - but each new SUSE Linux
release contains a new kernel and needs testing...

I've passed on the request to our engineers, they'll add this if time permits.

Resolving as fixed, since I put it into our feature database.