Hello,
A customer have some asymetric routing issues after a power outage on their local site. They are using MPLS as primary connection to their DC and a static L2L VPN connection as backup. There is a /18 network beeing anounced over MPLS from the DC. That /18 network is divided in multiple /24 subnets. For some reason after the power outage, they stoped getting specific /24 networks in BGP from the MPLS provider and instead the customer only saw the whole /18 network. This lead to that the backup L2L VPN started to establish IPSec tunnels and the traffic was goining out over the IPsec tunnel but came back on the MPLS interface, causing asymetric routing.
As a temporary solution, we disabled the VPN tunnel and the traffic started going over the MPLS interface again. This is not ideal ofcause, because we they cannot use the VPN as a backup no more. One thing that I noted, was they have the VPN tunnel configured to use reverse-route injection. I'm suspecting disabling this could be a workarround, but ot really sure if that would cause any other issues and the question still remains on why we dont see the more specific /24 networks in BGP.
Happy to know if anyone have any ideas on how to troubleshoot the issue.
Thanks
/Chess
