Draytek Vigor2620 Series Quick Start Manual page 28

Once the router has restarted, the WAN2 – Ethernet WAN interface can be configured
on the router, which is demonstrated in the following two sections.
Note
To reconfigure the P2 port for LAN use, go to [WAN] > [General
Setup] > [WAN2] and set the Enable option to No.
Once the router has been restarted to apply the change, the
port will operate in LAN mode.
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