zfs-fuse gone crazy, won't export, won't destroy pool

[mrluohua]

tl;dr zfs-fuse wont export nor destory my pool claiming 'busy', even when it's disks are used by mdadm raid!

So I had 4x3tb drives that I created a raidz pool on it for some temporary testing. When done, I was unable to export or destroy my pool

# zpool export -f rstoreb1
cannot export 'rstoreb1': pool is busy
# zpool destroy -f rstoreb1
cannot destroy 'rstoreb1': pool is busy

I can find nothing using it with lsof -n nor with ps -ef nor with fuser.

At this point I'm annoyed, and stop it with /etc/init.d/zfs-fuse stop

I partition the 4x3tb drives with parted, and create my raid with mdadm, and then create filesystem with mkfs.ext4, and mounted,

At this point mdadm is creating the raid, the new raid is mounted and I can copy files to it just fine.

I do a final reboot to make sure everything boots well and mounts well ... and low and behold ... zfs-fuse starts with boot, and mounts rstoreb1 again !

/dev/md127 7.9T 1.7G 7.9T 1% /extra/mdstore2
rstoreb1 8.1T 8.0T 89G 99% /extra/rstoreb1

these two raids are using the same hard drives !!

zpool stays it's healthy (i copied a 1gb file to the md127 raid device that shares the same disks with zfs raidz)

# zpool status
pool: rstoreb1
state: ONLINE
scrub: resilver completed after 0h0m with 0 errors on Sat Jan 5 17:55:15 2013
config:

NAME STATE READ WRITE CKSUM
rstoreb1 ONLINE 0 0 0
raidz1-0 ONLINE 0 0 0
disk/by-id/wwn-0x5000c5004e5454fe ONLINE 0 0 0
disk/by-id/ata-ST3000DM001-1CH166_Z1F16Q3S ONLINE 0 0 0 10K resilvered
disk/by-id/ata-ST3000DM001-1CH166_Z1F16QB0 ONLINE 0 0 0
disk/by-id/ata-ST3000DM001-1CH166_Z1F16QDX ONLINE 0 0 0

errors: No known data errors

at this point I am confused. I like fuse-zfs and I want to (need to) continue using it with my external e-sata drives but this internal set of disks I want mdadm, and zfs just won't let go.

How can I coax zfs to nicely let go of this volume?

# dpkg -l | grep zfs
ii zfs-fuse 0.6.9-1build1 ZFS on FUSE

I'm running Ubuntu 12.04.1 LTS.

note: I had uninstalled nfs-kernel-server at one point, and reading that it might be necessary I just reinstalled it (didn't start it), but I still can't destroy or export pool rstoreb1.

Any ideas? Thanks so much !!

mrluohua

edit: change zfs-kernel-server to nfs-kernel-server. There is no zfs-kernel-server, I typo'd it. I meant nfs.