Subject: Re: another RAIDframe oddity....
To: NetBSD Kernel Technical Discussion List <tech-kern@NetBSD.ORG>
From: Greg Oster <>
List: tech-kern
Date: 11/01/2003 13:42:51
"Greg A. Woods" writes:
> [ On Sunday, October 19, 2003 at 15:13:37 (-0600), Greg Oster wrote: ]
> > Subject: Re: another RAIDframe oddity.... 
> >
> > "Greg A. Woods" writes:
> > > BTW, is there any easy way to change the "Last configured as" value in
> > > the component labels? 
> > 
> > Not easy.. no.  (as in, no way to do it directly from raidctl)
> Hmmm.... another issue arose yesterday where this would also come into
> play, and where it's a lot less "cosmetic" than my initial situation.
> I had to move a RAID set from one host to another.  Now since the drives
> were hot-swap I was able to move them without rebooting.  However once I
> had them attached to the new system I had no way to autoconfigure them.
> Simply triggering autoconfiguration again, if there were a way to do it,
> would have caused a "collision" with the existing RAID set's device.
> I think it makes sense to consider supporting hot swap of whole RAID
> sets between systems.

If I can ever toss the old configuration code, the new configuration 
code would do the trick -- just tell it what components are involved, 
and it would figure out how they fit together.  Things like "where 
last configured" could be easily changed.

>  I think this means that besides having some way
> to re-trigger the RAIDframe autoconfiguration procedures there also
> needs to be some way to manually inspect the on-disk component labels of
> arbitrary specified disks, and there needs to be some way to adjust the
> "last configured as" name in those labels so that a "new" RAID set can
> be brought safely on-line without a reboot.  Of course already
> configured devices must be ignored when autoconfiguration runs too.
> There may be other issues, but that's what comes to mind initially.

As above, if the autoconfig code can be used for regular 
configuration (i.e. 'raidctl -c' and 'raidctl -C') then this will 
work.  I had a stab at changing it a couple years ago, but the 
various configuration bits are fiendishly interwoven, and successfully 
removing the old config bits without killing the patient appeared
too difficult at the time...


Greg Oster