Hi roberc,   The best option to troubleshoot here would be to use the packet captures tool in dashboard, found under Network-wide > Packet capture. Taking a capture on the Internet and Site-to-Site interfaces of the VMX should show traffic from the S2S VPN clients into Azure or vice versa, and depending on which traffic you see you can troubleshoot accordingly. If you need assistance with the investigation, I would recommend opening a support case with Meraki support, if you haven't already. Details on how to raise a case through dashboard or to call the support line can be found within the 'Get help & cases' page which is accessible in the ? icon menu in dashboard.   Regards, Mark_S ... View more