LAB Implement Application-Aware Routing

LAB Implement Application-Aware Routing

Task : 

• Implement an AAR policy to influence path selection based on link quality.

• Verify a new AAR policy.

Topology:

Solution

An AAR policy matches different applications with an SLA, which includes the data plane tunnel performance characteristics that are necessary to transmit the data traffic of the applications. The primary purpose of an AAR policy is to optimize the path for data traffic that WAN Edge routers transmit. The purpose of this task is to define an AAR policy, which dynamically chooses the uplink for VoIP traffic, based on link performance.

In vManage, open the Real Time tool for BR2-Edge1 from the Monitor > Devices dashboard, and display the App Route Statistics real-time data.

From the vManage main menu, navigate to Monitor > Devices and choose BR2-Edge1. Open the Real Time tools, and from Device Options, choose App Route Statistics. Do not filter the results.

Scroll to the right and review the reported link quality statistics (Mean Loss, Latency, and Jitter). The reported loss, latency, and jitter should be in the range of 0 to 3, although the numbers may differ. Make a note of the current mean latency for the Multiprotocol Label Switching (MPLS) transport. You will configure a policy that defines which actions to take based on these measurements.

Run a flow simulation on BR2-Edge1, and verify the current path in VPN 10 from Branch 2 to the DC-PC (10.10.2.10).

From the left pane, choose Troubleshooting tools and open Simulate Flows.

Configure the flow simulation as follows:

• VPN: VPN – 10

• Source/Interface for VPN – 10: GigabitEthernet4 – ipv4 – 10.2.2.1

• Source IP: 10.2.2.1

• Destination IP: 10.10.2.10

Click Simulate to start the simulation.

You should see the traffic go over the local MPLS transport; this is because of the traffic engineering policy from the previous lab. However, the traffic engineering policy strictly routes the traffic over the MPLS transport, regardless of the transport performance.

In Cisco vManage, navigate to the groups of interest for centralized policies. From the vManage main menu, navigate to Configuration > Policies, and from Custom Options, choose Lists in the Centralized Policy column.

Modify the existing Voice-And-Video SLA class. 

Click SLA Class in the left pane and edit the existing Voice-And-Video SLA class. Configure the list with the following values and click Save.

• Loss: 20

• Latency: 500

• Jitter: 250

In vManage, navigate to centralized data policies and create a new AAR policy. From the Custom Options menu, choose Traffic Policy from the Centralized Policy column.

On the Application Aware Routing tab, click Add Policy and choose Create New.

Provide a name and description for the AAR policy as follows:

• Name: AAR_Policy_v1

• Description: Application Aware Routing Policy

Click (+) Sequence Type to add the App Route sequence type to the policy.

Click (+) Sequence Rule to add a new rule. Configure the rule as follows:

Match:

• DSCP: 46

Action:

• SLA Class List

  1. SLA Class: Voice-And-Video

  2. Preferred Color: mpls

  3. When SLA not met: Load Balance

Click Save Match And Actions to save the rule. Click Save Application Aware Routing Policy to save the policy.

Navigate to the centralized policies and open the existing centralized policy (My_Centralized_Policy_v1) for editing. First, verify that the AAR policy is created. Then, click Centralized Policy to navigate back to the centralized policy dashboard.

Open the more options menu (…) from My_Centralized_Policy_v1, and choose Edit.

Import the created AAR policy into the centralized policy. Choose the Traffic Rules tab at the top of the page. Under Traffic Rules, on the Application Aware Routing tab, click Add Policy and choose Import Existing.

Choose AAR_Policy_v1 from the Policy list and click Import.

Configure the AAR policy application. Apply the policy to the Branches sites for the Corporate VPN (10).