Draytek Vigor2620 LTE Series User Manual page 101

After finished the above settings, click OK to save the settings.
Below shows an example for successful IPv6 connection based on 6in4 Static Tunnel mode.
Vigor2620 Series User's Guide
for pinging.

TTL (Time to Live) –If you choose Ping Detect as
detection mode, you have to type TTL value.
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