How Pfr inject the routes in IWAN

[hasunm522]

Hi,

Does anyone know how pfr inject routes to the border routers in IWAN solutions. I know it measures the performance of the channels using IP SLA Jitter probes and keeping a table based on traffic-classes. After  traffic comes it chooses the best exit interface based on those information and route the traffic through the preferred path defined or fall back to the other path if it exceeds the policy threshold values. I need to know how master control tells to border routers to use this path over eigrp learnt routes in the routing table.

Thanks,

[Joseph W. Doherty]

My experience with PfR predates the later PIRO variants, but assuming it works similar as it did, the MC injects routes on the border routers it manages, basically overriding whatever the existing routing is for particular destinations.

[Vasilii Mikhailovskii]

Hello.

PFRv3 does not inject routes into routing table. Instead PFRv3 injects itself into CEF path, so it may override FIB.

If you are asking about decision enforcement, it works like following:

• MC makes a decision based on data received from performance monitors
• MC notifies BRs about decision;
• BR enforces the decision[s] in CEF path;
• if traffic (from LAN) enters BR1, while should take WAN interface on BR2 - it's forwarded to BR2 over mGRE tunnel (created automatically).

Best regards,

[n.oneill]

Hi Vasilii

Is there a command to view the route overrides that IWAN/PfRv3 has implemented?

[Tenisist]

it is :

show ip route overrides pfr

some older implementation used dynamic route-maps with pbr though.