Ubuntu 15.10 Error about vnstat

[vergoh]

How was vnStat installed, from a binary or source package? From where and which version?

[scriptzteam]

Firstly via apt-get, then apt-get remove (not updating itself, not saving history, v1.11)...

Then From github (git clone ....) then ./configure ... make .... make install, there i got that error "d to restart vnstat.serv"

after error i then removed it and installed via apt-get install again

#vnstat --help
vnStat 1.11 by Teemu Toivola

and now the database does not updating itself, also it is resetting every day so no history is saved for past days...

[vergoh]

I suspect the first apt-get remove may have marked the service file as masked instead of removing it (remove <> purge) in order to avoid even trying to start the service. It may also have left the database directory and possibly database files untouched. You most likely would have needed to execute something like systemctl unmask vnstat after the make install command to get the service file reactivated, assuming it was indeed left behind.

Did you also remove the database directory before using apt-get install again? If that isn't the case then most likely the database directory still existed and was owned by root. If I recall correctly, the apt-get provided package runs the daemon with then vnstat user so it wouldn't have access to write database changes to the directory.