We have created IPSEC Tunnel between CISCO ASA and Azure cloud. but some time it is automatically down and traffic not passed. when tunnel down we initiate traffic from ASA and and tunnel up. why this happen.VPN and AnyConnect, IPSec
I came across issue with a client at Azure when we configured the vpn as policy based on the ASA this vpn was keep dropping into order to fix the issue we created a new vpn with route based never had issues since.
I guess in your case when there is not traffic in between these tunnel the tunnel tear down itself. there are few step you can take in account. keep the contant ping running from your end point (local network to remote network)