Firewalls being used – Sonicwall 3500 & Cisco 506e
Several months ago we relocated and it was then necessary to setup a Site to Site VPN tunnel with another network. (In this instance the other network was not directly managed by us)
Upon the creation of the tunnel and after successful traffic tests all looked well. However after several hours or less in some cases traffic stopped flowing yet both firewalls reported the tunnel as “up”.