makeing regular snapshots of a ZFS filesystem

I've used a valuable tool found on Tim Fosters Blog.

It is named zfs-autosnapshot. After downloading the package you
compile it with make and after this install the generated package.

After this there are some entrie in the crontab table for executing the
snapshots.

But to allow this you have to set a property on the filesystem from which you
like to take a snapshot.
The services in the SMF have also some options to finetune.

In this way I have set some filesystem to do a daily snapshot and preserving
7 Snapshots.

Have a look at the blog.