Cisco ACI L3Out and ACI Spine/Leaf Switch Route Summarization

[apfeil]

I have an L3out connected to a firewall with OSPF configured in a normal area which is not 0. I am learning all of the area routes as expected. Is it possible to summarize the routes to the spine switches/other leaf switches in ACI?

Firewall (OSPF Area1)--> ACI L3out Leaf Switch 1&2 (OSPF Area1) (learns all routes in same area from firewall)

Leaf Switch 1&2 Advertise the routes to spine and other leaf switches that are using the same Tenant. The other spine and leaf switches are not participating in OSPF, but they learn all of the routes.

Any assistance is greatly appreciated.

[Ezzedine]

convert the area to Stub area

[AshSe · Accepted solution]

While configuring L3Out Network; you get the option to create "Route Summarization Policy" under External EPG convass. Check:

[Ezzedine · Accepted solution]

• Route Summarization at the L3Out External EPG Level:

  This configuration of route summarization at the L3Out External EPG Level allows route summarization towards external L3Out peers only.

• Route Filtering and Aggregation at the VRF Level:

  Beginning in the Cisco APIC 5.2(4) release, Cisco APIC also provides option to perform route filtering and aggregation of routes that are advertised in a fabric to reduce the scale requirements of the fabric. This feature is configured at the VRF level. Enabling route summarization at the VRF level helps to achieve summarization of routes into the ACI fabric, as well as towards external BGP L3Out peers.

[apfeil]

One thing that I did find out is that the normal OSPF rules of all routes in one area are learned on all routers in that area apply. ACI will not let you get around the rules of OSPF.