What is important is the subnet mask assigned to the vpn client because potentially if the mask covers your internal subnets as well, then vpn client will try to ARP for it since they are in the same subnet when trying to access those internal resources.
How can I configure SSL VPN/NetExtender for clients with SSL VPN or NetExtender enables us to access the corporate SonicWall LAN subnets over the Internet with secure VPN tunnel. Sometimes the SonicWall LAN subnet and the client's IP on which the NetExtender is installed overlap and in such scenario accessing SonicWall LAN resources is not possible. UniFi - USG/UDM: Configuring L2TP Remote Access VPN This route will depend on the Gateway IP / Subnet that you specify for the L2TP VPN in the UniFi controller settings. The following classful routes will be added based on the subnet used for the L2TP VPN: 10.0.0.0/8 L2TP VPN subnet is configured with a 10.x.x.x address, for example 10.10.1.1/24.
Solved: Client vpn dhcp - The Meraki Community
How do you deal with VPN access that has the same subnet
Can't reach subnet across VPN - Networking - Spiceworks
VPN problems when remote subnet is the same as the VPN