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WAN Aggregation Recommendation

We had a Cisco stacked 3750 as our core/distribution in a collapsed model and we replace it with 2 Cisco Nexus with vPC/HSRP/OSPF/static ip route summarization taking over the core/distribution role and also hosting our VMWare ESXi and SAN. However we never move our WAN/VPN and internet edge routers backbone connection to the new Nexus core/distribution switch. Our edge WAN/VPN internet routers consist of Cisco, Vyos (on DECISO hardware) and UBNT Edge Router Pro.


Recently we had power issue with the primary device in the stacked Cisco 3750 and we loose connection to some device connected directly to it. So to eliminate single point of failure I want to move the backbone connections of all our edge WAN/VPN internet routers to the Nexus and have redundant backbone connection distributed to the two Nexus with VRRP/HSRP configured on the edge WAN/VPN internet routers


What other advantages will I gain from this and is there any disadvantage of aggregating the WAN to the core/distribution ? Is it a good idea to move my WAN backbone connection to the core/distribution switch/router ?


Current and propose setup attach herewith

Jon Marshall
Hall of Fame Guru


You are not really comparing like with like. 


Your new setup shows dual connections from all your WAN devices which you could just as easily do on your 3750s if you wanted to. 


Either way just make sure you have dual connections from both and you would have the redundancy you need. 



Thank you @Jon Marshall 

New setup as follows with the default ospf cost however I did adjust the OSPF cost on the SVI interface. I know OSPF supports equal-cost load balancing but shall I leave them as default ? i.e SVI ospf cost will be both 40 on both Nexus. I've got HSRP setup on the SVI's with 2 of the 8 VLAN's dedicated my servers and the other VLAN's hosting clients and other stuff. All hosts in these VLAN's uses the  SVI's HSRP IP address as their gateways  


Wont I create any routing issue between my remote hosts and clients connecting to the servers ? 22072020-Core-OSPF-Cost-Suva.JPG