L2tp + ipsec server on ubuntu 14.04 - how to burn multiple ipsec users?

Question

VPN

The problem is, I created several users here /etc/ppp/chap-secrets
for example:
user1 l2tpd 12345 192.168.8.3
user2 l2tpd 54321 192.168.8.4
user3 l2tpd 21212 192.168.8.5
Then I created ipsec keys for them:
For example:
192.168.8.3 %any : PSK "12345678"
192.168.8.4%any: PSK "87654321"
192.168.8.5%any: PSK "12341234
" What is the problem? how to solve?