[dm-devel] Re: LVM on dmraid breakage

[Phillip Susi]

Luca Berra wrote:
> And by activating a vg manually i don't benefit from the filter? why?

Huh?  I fail to see the direction you are going in with this and what it 
has to do with udev auto configuring things.

> What about if it is a ha-cluster suite that needs to activate the volume
> group. I can't have udev activate that on sight, it will probably
> corrupt data.

Right, which is why you wouldn't be using udev in such a set up.  At 
least not configured to auto mount disks when plugged in.

> probably because this is the only available way now.
> anyway this method tends to suck when you have a complex setup.
> and lvm device filters are not very intuitive to setup.

You just made my point for me.

> Let's make a deal, you code that in udev, and in the meantime try to
> convince Linus in ditching partition detection code from kernel.
> I will code the filter for current lvm.

The partition table code already can be disabled in the kernel config 
iirc.

> doing this will require changing how lvm tools work.
> 1) disable the automatic vgscan performed by every lvm command
> 2) modify pvscan to be able to scan a single device

Correct.  The commands need to be able to take a list of devices to 
manipulate rather than going after /dev/sd*.