Draytek Vigor2912 Series User Manual page 264

When you choose L2TP over IPsec (Nice to Have) or L2TP over IPsec (Must), you
will see the following graphic:
Available settings are explained as follows:
Item
Profile Name
VPN Dial-Out
Through
Vigor2912 Series User's Guide
Description
Type a name for such profile. The length of the file is
limited to 10 characters.
Use the drop down menu to choose a proper WAN interface
for this profile. This setting is useful for dial-out only.
WAN1 First/ WAN2 First/ WAN3 First - While
connecting, the router will use WAN1/WAN2/WAN3 as
the first channel for VPN connection. If
WAN1/WAN2/WAN3 fails, the router will use another
WAN interface instead.
WAN1 Only /WAN2 Only/WAN 3 Only- While
connecting, the router will use WAN1/WAN2/WAN3 as
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