[Ocfs2-tools-devel] [PATCH] Option to skip cluster checking in tunefs.ocfs2

[Joel Becker]

On Sat, Oct 17, 2009 at 12:51:07PM +0200, Lars Marowsky-Bree wrote:
> On 2009-10-17T11:51:40, Jan Kara <jack at suse.cz> wrote:
> >   I have to admit I don't understand the details here. Lars just told me
> > to implement it, so I did ;). From what Lars told me, I understood
> > there are problems with supporting some kind of cluster stack and solving
> > them requires non-trivial changes to kernel-userspace interface and that's
> > going to take time. Therefore I've implemented this option as a temporary
> > band aid for admins.
> >   I've CC'd Lars so he might give you more facts :)
> 
> That's correct. (Remember the LVB size issue?)

	I'm not sure what you mean.  Are you saying that SLES isn't
going to take the fix for the LVB size issue?

> It also seemed impossible to alter the fs while umounted and with the
> cluster stack wholly stopped, which seemed like a desirable feature.

	It's not desirable, because you don't know that it is stopped
elsewhere.  The only way to know is to have the stack up and check.
	Essentially, we make every effort to ensure that we don't lose
people's data.  This includes making it hard for them to shoot
themselves in the foot.  Now, there are places we can't avoid it.  But
we try to restrict ourselves to only those places.

> If mkfs.ocfs2 has a -F option, I think tunefs.ocfs2 can handle one too.

	This is a good example.  tunefs.ocfs2 modifies existing, live
filesystems.  Whether mounted or not, it is expected that the data on
them will be used in the future.  mkfs.ocfs2, conversely, is expected to
wipe the filesystem.  You're already asking to wipe, so if we let you
wipe, it's as expected.  A tunefs operation, on the other hand, is
expected to result in a clean filesystem.
	There are a couple of things that cannot be done with the
cluster active.  In tunefs.ocfs2, we provide specific options for those.
Thus, only those can be invoked in a non-cluster-coherent manner.

Joel

-- 

Life's Little Instruction Book #444

	"Never underestimate the power of a kind word or deed."

Joel Becker
Principal Software Developer
Oracle
E-mail: joel.becker at oracle.com
Phone: (650) 506-8127