Hi all,

I'm having loads of trouble with check-gateway functionality on ipip tunnels.
My CCR has 150-160 ipip tunnels with static routes for different subnets for every one of these tunnels. These static routes have check-gateway=ping enabled (for backup link purposes, but this is of no importance for the matter).
Problem is that without any visible reason (logs show nothing), some of the routes become unreachable (random amount of random routes). Even though they became unreachable, I can still ping the other end-point of the tunnel from the terminal. After couple of minutes these routes get back to being reachable again. If I disable/enable problematic route, it becomes reachable instantly.
This route flapping happens constantly.
CPU is as 0% (very small amount of traffic) and there is about 3.5GB of RAM free.
I have tried with different OS versions, but the same thing happens.

Is this known issue? Has anyone else experienced this kind of problem? Any solution?