How to log vpn access

[maurotb]

Hi,
i have setup a openvpn with 2fa and local auth.

1)I need to have a log of login/logout and login failure how to?
2)is possible to launch a command on login/logout?
is usefull to launch zabbix-send to remote log and monitoring access
3)is possibile to send snmp trap on login/logout/login failure?
Thanks