Zs and openvpn work perfectly together , from which S.O. are you trying to connect ? This is one of my configuration files , (host is win) and openvpn client is OpenVpn 2.3.2
remote xx.xx.xx.xx 1194
proto tcp
auth-user-pass
ca myCacert.pem
cert myusercert.pem
key myusercert.pem
#verify-x509-name 'OU=Hosts, CN=cn_on_certificate'
remote-cert-eku 'TLS Web Server Authentication'
#cipher AES-128-CBC
#auth RSA-SHA512
comp-lzo
verb 3
mute 20
resolv-retry infinite
nobind
client
dev tap
persist-key
persist-tun
auth-nocache
script-security 3
route-method exe
route-delay 2greetings