Nexus 7k - OSPF over Peer-link

[Steev112]

Hi all,

I am not sure if this scenario will work or not, I want to enable OSPF over Peer-Link, my scenario is I have three locations :

 location#1 has two nexus 7k configure one VDC connected over peer-link.

Location#2 has one core switch 6500 connected to Nexus 7k over trunk and enable OSPF over Vlan 66

Location#3 has one core switch 6500 connected to Nexu7k over trunk and enable OSPF over vlan 55.

I want to enable OSPF over peer-link to carry subnets over OSPF as showing in the diagram.

How can achieve this setup?

Thanks

[Steev112]

hi ,

i updated the diagram,

also there is one switch connected to two Nexus using L3 interface and enable OSPF as showing in the diagram,

how can achieve this setup, am care of Peer-link , can i enable ospf over it and the ospf will work fine, or i need extra cable between the two nexus using L2 and enable ospf for this link or L3 link

thanks,

[Steev112]

and there is link between location#2 and location#3 and i will run ospf.

i am confusing only i need enable OSPF over peer link by using SVI or i need alos add external link and enable OSPF.

if any one can help me for this setup.

Thanks

[Bilal Nawaz]

Hi Steven, I would highly recommend using another link that is separate point to point connection between N7K's for routing, although it will work with SVI's on the N7K's via the Peer link. It just depends if you have spare ports to use for routing - I prefer using separate L3 interface for routing, a matter of preference. Having said this there are some scenario's where this is not supported depending on configuration and set-up.

If you do take the latter option of using SVI's over the peer link, then please use ospf network type to be point-to-point with /30. It is totally supported by Cisco.

Best practice:

• Attach external routers or L3 switches with L3 routed interfaces.
• It’s OK to use the vPC peer-link to form a routing adjacency between the two Nexus 7000′s.  Use a VLAN dedicated to the routing adjacency and only forward this VLAN on the peer-link, not on the vPC member ports.
• Use the ‘passive-interface default’ command in your routing protocol to prevent a routing adjacency on all the other VLANs.
• If attaching external devices on a Layer 2 port running a routing protocol with the Nexus 7000′s (e.g. firewall running OSPF), provision a new non-vPC inter-switch link, and attach the device to non-vPC VLANs.
• Use static routes to the HSRP gateway address on external devices such as firewalls and load balancers.  Do not run routing protocols on these devices unless absolutely necessary.

If you have point-to-point adjacencies then you should have no problem at all. 

[Bilal Nawaz]

Hi Steven,

I can see you have posted about the same topic/question several different posts on other threads, please refrain from doing this.