SD WAN ( Viptela) Scenario

[Jackyhope]

Hi everybody,

I am trying to learn viptela based SD WAN.

Please consider the following example:

Above:

1) We have some locations connected via PTP link, All routers are Vedge routers and running OPM with vsmart ( not shown)

2) We have certain application at NYC that needs to talk 10.2.2.0/24 subnet at LA.

3) Consider the traffic flow from NYC to LA router only, we have application aware routing  with following criteria:

Use TLOCA  ( Verizon CKT_ to reach 10.2.2.0/24, if TLOC A is hitting 80% utilization, use TLOCB ( Qwest )

4) Currently, traffic from NYC destined to 10.2.2.0/24 is flowing  NYC-R1->DC-R1-->TLOCA-LA-R1

5) TLOCA utilization hits 80%, NYC therefore start using TLOCB to reach 10.2.2.0/24. Traffic follows the path:

NYC-R1--DC-R1--PA-R1---TLOC B-LA-R1

6) Assume link between DC-R1- AT&T PTP-PA-R1 is saturated, but we are not tracking that for our application aware routing which is only tracking utilization on TLOC at destination edge routers, how do we cope with such scenario?

Thanks and have a good night!! 

[Kanan Huseynli · Accepted solution]

Hi,

in AAR, if you don't do check "strict" option, then traffic will be routed based on routing if no path passes SLA check. Routing is fallback method, unless "strict" option is checked. Because, it means "drop traffic if no path passes SLA".

https://www.cisco.com/c/en/us/td/docs/solutions/CVD/SDWAN/cisco-sdwan-application-aware-routing-deploy-guide.html#Design

●     Strict – if enabled, the selected data traffic would be dropped if any of the WAN transport(s) doesn’t meet the specified SLA.

For all other data traffic that doesn’t match the selected application/traffic list, the traffic would be load-balanced across all the available WAN transport links available on the WAN Edge device.

HTH,