Hallo, 
I've Switches Managed in VLAN 1. and a S2S VPN connection between 2 Sites. At the Customer site there is the Radius Server. Now my question. 
VLAN 1 must be in VPN Mode disabled otherwise i lose connectivity to the Switches. 
Is it necessary that the Switches reach the Radius Server wich is at the other site from the VPN. 
thanks for your ideas/help
René