ACI l3out ospf and static route

[binoyb]

We have ospf set on a leaf 101 ( DC1)  to legacy router at DC2 , we want to have static route for specific host to remote side , I see that is done from the existing ospf L3out --noide profile leaf 101 and add static route ,the static route will take precedence due to the AD , is that right way

Note: There is a reason for this static route as there are multiple WAN link between DC and there is a requirement to do static without any manipulation of route with cost. 

eg: DC1 ( 1.1.1.0/24) SVI 1.1.1.1 ------L2 WAN ---L3out1 - ACI Leaf 101 port 1/7-Routed port  (10.1.1.0/24)-OSPF

                                             * want to add static to same l3out1 along with ospf          L3out1 - node profile (101) add 1.1.1.7/32 GW 1.1.1.1

Please let me know if this is right way , what to know if we can have both ospf and static route on the same L3out ?

Regards,

BB

[marce1000 · Accepted solution]

 - It is possible to have both OSPF and a static route on the same L3Out in ACI. Adding a static route for a specific host to the remote side is a valid approach, especially if you have specific requirements, such as multiple WAN links and the need to manipulate routes with cost.
In your scenario, you have OSPF configured on Leaf 101 (DC1) to a legacy router at DC2. If you want to add a static route for a specific host (1.1.1.7/32) to the same L3Out (L3Out1), you can do so by modifying the node profile (101) associated with that L3Out.
The static route will take precedence over OSPF due to its administrative distance (AD). The AD for OSPF is typically 110, while the AD for a static route is usually 1. Therefore, the static route will be preferred for the specific host, and OSPF will continue to handle the remaining routing for other networks.

Here's an example of how you can add the static route on the same L3Out:

Access the ACI fabric management interface.
Navigate to the appropriate L3Out configuration.
Modify the node profile (101) associated with L3Out1.
Add the static route entry for the specific host, specifying the destination network (1.1.1.7/32) and the next-hop gateway (1.1.1.1).
Save the configuration changes.
By adding the static route in the node profile, you ensure that it is associated with the L3Out and will take effect for traffic passing through it.

Remember to consider any potential impact on routing stability and convergence when introducing static routes alongside dynamic routing protocols like OSPF.

M.

[binoyb]

Excellent , That was what I was thinking but I wanted some confirmation as this needed to be done on a production environment, I was sure that we could not do two different routing protocol on same L3out ,  thanks for the reply Marce and the explanation , it would be helpful for others too 

BB