Make sure the debug dump option is not used -- otherwise it will crash pppd.
/etc/ppp/options.l2tpd.client:
ipcp-accept-local
ipcp-accept-remote
refuse-eap
require-mschap-v2
noauth
mtu 1200
mru 1200
noipdefault
debug
defaultroute
usepeerdns
connect-delay 5000
name <username>
password <password>
/etc/ipsec.conf:
# ipsec.conf - strongSwan IPsec configuration file
# basic configuration
config setup
# strictcrlpolicy=yes
# uniqueids = no
# Add connections here.
# Sample VPN connections
conn %default
ikelifetime=60m
keylife=20m
rekeymargin=3m
keyingtries=1
keyexchange=ikev1
authby=secret
ike=3des-sha1-modp1024!
esp=3des-sha1!
conn myvpn
keyexchange=ikev1
left=%defaultroute
auto=add
authby=secret
type=transport
leftprotoport=17/1701
rightprotoport=17/1701
right=<IP address>
