My company has 2 locations and we have an MPLS connectivity between them. We are running a static route to the service provider's PE and MPLS starts from there. Now the issue we face is that if there is any backbone issues in provider's network, we won't be getting any logs on CE and hence calculating the downtime has become an issue.
I think implementing GRE tunnel between both the sites can be a good solution for this issue. Just a query I have is that whether backbone issues in Service Providers network would give me GRE Tunnel Up/Down logs in my CE.
Lost of connectivity between the two PEs would indeed cause the GRE tunnel interface to go down, assuming that you configure tunnel keepalives as follow: