gvinum question: why are subdisks not attached?

[Ian Jefferson]

Howdy,

On Jun 26, 2006, at 9:39 AM, Travis H. wrote:

> Hiya,
>
> I finally resolved the source of my gvinum problems.  Every time I
> reboot, the plexes and volumes come up attached to one another, but
> both are size zero and the subdisks exist but are not attached.  Has
> anyone a guess about the source of this problem?

One possibility is your partition type.  I'm not certain. (see below  
on my bsdlabel output sample)  I was working on a Raid5 configuration  
and finally did get it working.  I have a few suggestions.

One is to try to find to find old vinum documentation.  What finally  
brought clarity to me is looking at the vinum man pages from FreeBSD  
4.7.  It has a lot more information vinum(8), including a nice  
section on the config file format and examples.  Of course I could  
have just missed it (nope just checked again).

The second is to try marking your partitions as type vinum.

The third is to drop the slices since the configuration that worked  
for my Raid 5 set used just partitions no slices (see below).

The fourth is to move up to 6.1.  I did this during my struggles but  
I don't think that was my issue.  However 6.1 does have improved man  
pages :-), but not as good as the 4.7 pages.  You have to read both  
because gvinum doesn't implement the full vinum command set.  I  
*think* the config file is the same though.

# /dev/ad4:
# same as /dev/ad8 and /dev/ad10 for a Raid 5 3-disk system.
8 partitions:
#        size   offset    fstype   [fsize bsize bps/cpg]
   a: 390721952       16    unused        0     0
   c: 390721968        0    unused        0     0         # "raw"  
part, don't edit
   d: 20971520        0     vinum

Finally, enough people have been able to get/claim vinum success to  
make me believe it's OK.  There are two key issues in my mind.  I'll  
add that now that I found TFM I can RTFM.  ;-)

#1 it is a little fragile (ie not idiot proof enough yet for this hack)
#2 the documentation needs some work ... but that's kind of up to us  
now isn't it...

I think I owe Freebsd-docs a long post but I have another 20 hours of  
understanding and playing to do at least.  This is a great capability  
for small systems.  Frankly I'm a bit puzzled by geom and why the  
change was made from whatever it replaced.  Overall 6.x looks like a  
step backwards from a filesystem management perspective... maybe  
someone could comment on geom... perhaps a future enabler?

Ian