GX400 VPN Keepalive issue

Try this configuration:
from the Wan/Cellular tab(at top) - Keep Alive ->
Keepalive IP Address
The IP address that the AirLink gateway pings to determine if there is Internet connectivity and to
make sure the IP address is accessible.
Enter the IP address or fully qualified domain name for the AirLink gateway to ping to keep itself alive
(online). Options are:
• IP address
• Domain name
(page 70 of instruction guide)

Thanks,
J.