OMV 6 Issues with the ZFS plugin - cannot destroy 'pool0/ISOs': dataset is busy

Am trying to destroy a data set on a ZFS by running the following command:

zfs umount pool0/ISOs

cannot unmount 'pool0/ISOs': not currently mounted

zfs destroy -r pool0/ISOs

cannot destroy 'pool0/ISOs': dataset is busy

grep pool0/ISOs /proc/*/mounts

/proc/2654/mounts:pool0/ISOs /srv zfs rw,mand,xattr,noacl 0 0

is this a bug with the pluggin that will not allow you to delete pools after creation? please kindly advise. THanks.

Thank you all for your reponses. Please note that I don't intend to delete the complete pool. I need to delete the data-set under the pool:

in other words, I just want to delete the folder called ISO's..

root@Pegasus:~# zpool destroy pool0/ISOs

cannot open 'pool0/ISOs': invalid character '/' in pool name

use 'zfs destroy' to destroy a dataset

root@Pegasus:~# zpool destroy -f pool0/ISOs

cannot open 'pool0/ISOs': invalid character '/' in pool name

use 'zfs destroy' to destroy a dataset

root@Pegasus:~# zfs destroy -f pool0/ISOs

cannot destroy 'pool0/ISOs': dataset is busy

Thank you kindly for all your advise.

I tried deleting the data-set from the GUI and the following error occurred:

root@Pegasus:~# zfs list -t snapshot

NAME USED AVAIL REFER MOUNTPOINT

pool0@2022-08-24_01-52-43 85.2K - 128K -

root@Pegasus:~# zfs list -t snapshot

no datasets available

then retried and...

root@Pegasus:~# sudo zfs destroy -Rrfv pool0/ISOs

will destroy pool0/ISOs

cannot destroy 'pool0/ISOs': dataset is busy

This is looking to me as an issue with the file-system itself or the way the plugging enters the information in the fstab file. there are no snapshots of the system and interestingly, I was able to delete the single snapshot that there was directly from the GUI.

https://linux.die.net/man/3/getmntent

this is the error that the OMV 6 GUI is giving me:

No such Mntent exists

OMVModuleZFSException: No such Mntent exists in /usr/share/omvzfs/Utils.php:84

Stack trace:

#0 /usr/share/openmediavault/engined/rpc/zfs.inc(312): OMVModuleZFSUtil::deleteOMVMntEnt(Array, Object(OMVModuleZFSFilesystem))

#1 [internal function]: OMVRpcServiceZFS->deleteObject(Array, Array)

#2 /usr/share/php/openmediavault/rpc/serviceabstract.inc(123): call_user_func_array(Array, Array)

#3 /usr/share/php/openmediavault/rpc/rpc.inc(86): OMV\Rpc\ServiceAbstract->callMethod('deleteObject', Array, Array)

#4 /usr/sbin/omv-engined(537): OMV\Rpc\Rpc::call('Zfs', 'deleteObject', Array, Array, 1)

#5 {main}

no there are no SMB shares enabled. i have the dire feeling am going to have to reinstall OMV or use something else to address this issue.

I was able to figure it out.

this is the solution:

1. Make sure that nothing is pointing or being mapped to the data /pool/dataset "or" /pool when you are trying to delete a dataset like a home folders or shares for any users under the pool. in my issue proftpd was using a folder under the pool as a temp directory.

if you have your home directories under your /pool dataset. you will have to disable it on OMV for the deletion to work.

use the command : smbstatus --shares

to view that you have no shares being used.

you can also run: mount -v to view what you have mounted on the system.

umount to unmount

if there are any mounts for the /pool and unmount them. once completed

run the following command to allow the data set to be deleted: zfs set canmount=noauto /pool/dataset

reboot this is important.

Once the machine is started run the following: zfs destroy -Rrfv /pool/dataset

this will delete the desired data-set.

Run in the terminal : zfs list

this will show the list of data-sets available excluding the one recently deleted.

run : zfs set canmount=on dataset
this will allow the OMV6 to auto mount the files-system once rebooted again.

thanks to: https://unix.stackexchange.com…-snapshot-dataset-is-busy