There's a known issue with MX's on v18.107 that in certain scenarios when you have a HA pair, if you make changes, it causes services to restart, including VPN's.   There is an internal case at Meraki and my case is linked to it.   The details i got told were:   Certain changes have been seen to cause services to restart, causing VPN tunnels to drop and reform when running an HA pair of MX’s on firmware version 18+:   Firewall rules changes DHCP scope changes Layer3 changes to VPN-enabled subnets/routes Bringing up disconnected WAN2/Cellular interfaces from the “disconnected” status Enabling or disabling content filtering I'd raise this with Meraki so it gets linked to their internal case. ... View more