I found these entries in system log. No idea if they are the problem or not.

12:49:04 2018 daemon.warn openvpn[21692]: WARNING: this configuration may cache passwords in memory – use the auth-nocache option to prevent this
12:49:05 2018 daemon.warn openvpn[21692]: WARNING: ‘link-mtu’ is used inconsistently, local=‘link-mtu 1558’, remote=‘link-mtu 1542’
12:49:05 2018 daemon.warn openvpn[21692]: WARNING: ‘cipher’ is used inconsistently, local=‘cipher AES-128-CBC’, remote=‘cipher BF-CBC’
12:49:05 2018 daemon.notice openvpn[21692]: [84122158241287d90752bc38970e4aea] Peer Connection Initiated with AF_INET:1198
12:49:11 2018 daemon.notice netifd: Interface ‘VPN_client’ is enabled

12:49:11 2018 local1.info Keepalived_vrrp[2155]: Netlink: filter function error
12:49:11 2018 local1.info Keepalived_vrrp[2155]: Netlink: filter function error