zfs snapshot management

[Emil Muratov]

>> Since there seems to be a fair number of serious zfs users here, I was
>> hoping for some further suggestions for use in either case.  Any 
>> input is
>> welcome...
>
> We've had plenty of good experiences with sysutils/zfs-snapshot-mgmt

I have had problems with this tool regarding daylight saving time 
changes and snapshot aging calculation. I wrote to the author but didn't 
get any response.
I used zfSnap (/usr/ports/sysutils/zfsnap) as a very good alternative 
for quite a long time, but now it's broken for v28 since zfs -r behavior 
for snapshots has changed. Hope there will be a fix for it someday.