Draytek Vigor2920n User Manual page 314

general settings in IPSec General Setup, such as the pre-shared key that both parties
have known.
3. Go to LAN-to-LAN. Click on one index number to edit a profile.
4. Set Common Settings as shown below. You should enable both of VPN connections
because any one of the parties may start the VPN connection.
Vigor2920 Series User's Guide
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