We have an endpoint connection on a context of a Cisco ASA 5515 for multiple clients and one day our PRTG showed many of the sensors being red. While it's possible the tunnels were down at some point they were definitely up when we did some checking afterwards, meaning that we actually have a red sensor for a functional tunnel. We tried readding the sensor but the PRTG either doesn't see the tunnel at all, meaning we cant actually find it to add it OR it sees it and we add it but it goes straight to red. We checked and most of them are ikev1 vpns. Also we still have some green and working tunnels on the same device.
We would appreciate any idea that e can test so we can fix this.
p.s. this has been working just fine for at least a year and there were no changes on either PRTG server or ASA device.