Re: dk for z/lvm volumes?

[mlelstv%serpens.de@localhost (Michael van Elst)]

gdt%lexort.com@localhost (Greg Troxel) writes:

>Once you export a zvol via iscsi, then it makes sense to methat the system
>attaching it sees it as a disk drive.

Yes. The zvol is seen as a disk image.


>> I couldn't coax dkctl to create dk devices for the gpt on the volume,
>> and dkctl seems like a bit of a mismatch for creating arbitrary dk:s
>> anyway as it seems mostly directed at bare drives (cache settings
>> etc).

>From the NetBSD point of view there is a zvol, and you are letting iscsi
>manage it.  So there's nothing to tell netbsd to read a gpt/mbr and
>deal.

Yes. The zvol is not a disk and doesn't understand partitioning itself.


>It seems sensible to me; vnconfig takes a file and tells the system to
>treat it like a disk.   I don't know if doing vnconfig on a zvol works
>right, but it doesn't feel broken.  Once you do this then if there is a
>gpt then the partitions should show up as dkN, I'd expect.

vnd can only handle files on a filesystem. It would be nice if it could
handle devices, but currently the code cannot handle that, so an attempt
is rejected.


>The other thing you can do is export the zvol snapshot via iscsi and use
>an iscsi initiator on netbsd to mount it.  I suspect this amounts to
>about the same thing as vnconfig.

iscsi presents it as a disk, just as it presents it as a disk to the
Windows machine.

There is another possibility. The old ccd(4) driver lets you use
a wedge as a component, it again presents the result as a partitioned
disk.

-- 
-- 
                                Michael van Elst
Internet: mlelstv%serpens.de@localhost
                                "A potential Snark may lurk in every tree."