forwarding-options {
    helpers {
        bootp {
            interface {
                vlan.2 {
                    server 192.168.215.10;
                    vpn;    <---- may be required if the DHCP is located on remote side of tunnel
                }
                vlan.3 {
                    server 192.168.215.10;
                    vpn;
                }
                vlan.4 {
                    server 192.168.215.10;
                    vpn;
                }
                vlan.24 {
                    server 192.168.215.10;
                }
                vlan.23 {
                    server 192.168.215.10;
                }
                vlan.22 {
                    server 192.168.215.10;
                }
                vlan.14 {
                    server 208.90.136.110;
                }
                vlan.13 {
                    server 208.90.136.110;
                }
                vlan.12 {
                    server 208.90.136.110;
                }
            }
        }
    }
}