[indiana-discuss] Frequent and Hourly auto-snapshot problem

[Tim Foster]

On Mon, 2009-02-02 at 08:07 -0800, Luis Useche wrote:
> Thank you for your answer.

Ok.

> I read the bug and it seems like you have to mount and unmount the
> "problematic" filesystems until the command "pfexec zfs snapshot -r
> rpool at snap" is successful. In my case, as expected, it raises an
> error:
> 
> luis at beer ~ $ pfexec zfs snapshot -r rpool at snap
> cannot create snapshot 'rpool/ROOT/opensolaris at snap': dataset is busy
> no snapshots were created
> 
> However, I don't know exactly what filesystem should I mount/unmount.

rpool/ROOT/opensolaris in this case (because it's the one the command
failed to create a snapshot on)

>  Moreover, I don't know how to do it.

Most of the time, you can do:

# zfs mount <dataset>
# zfs unmount <dataset>

if the dataset has a mountpoint property ("zfs get mountpoint <dataset>"
tells you what that is)  For the special zfs mountpoint "legacy", you
need to use a traditional mount/unmount command:

# mkdir /tmp/a
# mount -F zfs <dataset> /tmp/a
# umount /tmp/a


In the case of ZFS datasets used for the root filesystem, they have
mountpoints set to "/", so mounting them in this manner will fail
because your running boot environment is already mounted on "/".

So you need to tell it to mount elsewhere temporarily, eg.

# zfs set mountpoint=/tmp/a <dataset>
# zfs mount <dataset>
# zfs unmount <dataset>
# zfs set mountpoint=/ <dataset>


> Thanks again for your help.

No problem. Feel free to update the bug report with this information if
you think it could be helpful to others.

	cheers,
			tim

> Luis.