ZFS "cannot open [...]: dataset does not exist"

Niklaas Baudet von Gersdorff niklaas at kulturflatrate.net
Wed Dec 10 08:04:47 UTC 2014

Dear Mailinglist,

Niklaas Baudet von Gersdorff [2014-12-08 20:19 +0100] :

> I am currently using zfssnap.sh [1] to make a regular backup of
> the entire ZFS pool on our server. In principal, this works great,
> nevertheless, every time I am running the script I get the following
> error:
>     cannot open 'tank/usr/ports': dataset does not exist
>     cannot open 'tank/usr/src': dataset does not exist
>     1:  https://bitbucket.org/mmichele/zfssnap

I figured out that the problem is not ZFS itself but `zfssnap.sh`.
Please refer to my explanation at


In short, the default behaviour for `zfssnap.sh` is to exclude the
datasets mentioned above. Though, these datasets do not exist on the
server I am administrating. I was aware of that and tried to hand over
an empty `EXCLUDES` variable as it is explained in the programs

    If you do not want these excluded, pass an empty EXCLUDES envvar.


Unfortunately, handing over an empty environment variable does not work.
The solution is to use the following code

    EXCLUDES=" "

Be aware of the white space!



Baudet von Gersdorff
niklaas at kulturflatrate.net


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