Gmirror question - what am I doing wrong?

[Pawel Jakub Dawidek]

On Thu, Jan 27, 2005 at 12:05:29AM -0600, Karl Denninger wrote:
+> Now here's the problem.
+> 
+> Let's say that I have the system sync'd with the larger and smaller block
+> count disks online.  The SMALLER one fails.  I replace it, but the other 
+> larger disk is not available, because its in the vault.  I thus replace the
+> disk with the SMALLER one, but I can't attach the slice on the replacement 
+> disk, because that disk has a smaller capacity than the only remaining
+> active mirror component, and I can't make a slice bigger than the number 
+> of actual blocks that exist on the drive!
+> 
+> I'm screwed, and have no way out of this other than to ditch the entire
+> scheme, manually recreate the smaller volume, copy all the data over, and
+> restart gmirror from scratch.  

I need exact commands you use to perform this.
I did small simulation of your problem (if I understand it right):

I created three md(4) devices:

md0 - 12MB
md1 - 10MB
md2 - 10MB

Now, I create a mirror from two of them:

	# gmirror label foo /dev/md[01]

My mirror size is 10MB-512B.
Now I remove smaller component:

	# gmirror remove foo md1

And insert the second smaller component:

	# gmirror insert foo md2

Everything works for me.

Some more notes: When you create a mirror, gmirror takes the smallest
component's size as a size of the whole mirror, so you should be able
to insert new components which are bigger than or equal to the smallest
one (used for mirror creation).

-- 
Pawel Jakub Dawidek                       http://www.wheel.pl
pjd at FreeBSD.org                           http://www.FreeBSD.org
FreeBSD committer                         Am I Evil? Yes, I Am!
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 187 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-geom/attachments/20050127/ce354e17/attachment.bin