Not clear but R6300 does not have VPN termination so you will not able to use VPN tunnel when you are outside of your house/location
If you are use VPN Client behind the R6300 and reaching out to VPN server/ VPN router on remote location then you need to enable VPN passthrough. Also if you are using Cisco VPN client, sometime GRE protocol can be an issues for making the connection. I' not certain if R6300 support GRE protocol
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