Monitoring /proc/user beancounters via vzwatchd
vzwatchd monitors the /proc/user_beancounters file for changes and sends mail notifications.
vzwatchd is the daemon associated with the App::OpenVZ::BCWatch perl module, which is the successor of monbean.pl and thus marks it as obsoleted and deprecated.
See the module's CPAN page (link below) for further information.
Installing
Invoke the CPAN shell with
$ sudo cpan -i App::OpenVZ::BCWatch
to install the module and follow the instructions.
Once done, consult the docs of App::OpenVZ::BCWatch.