Hi Matus,
the rrdtool package uploaded to jessie today has a bug that prevents (at
least) smokeping and cacti from drawing graphs.
Yikes! I did the upload.
And whilst the smoke-test went alright, I didn't see that coming. I shall take a look at this.
The temoporary solution is to downgrade librrd4 from 1.4.8-1.2+deb8u1 to
1.4.8-1.2
I'll try to see if it could be fixed properly, otherwise the fall back would be to downgrade back to the previous version.
Thank you for reporting this :)
Best,
Utkarsh