Cisco Cisco MGX-FRSM-HS2 B Serial Frame Service Module Libro blanco

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White Paper

Figure 1. WAAS Flow Agent (FA) Data Collected from Various Points Along Server/Client Path

Client

Edge WAE

Core WAE

Server

Core FA

NAM

TCP 1

TCP 2

TCP 3

ClientLAN

ClientWAN

ServerWAN

ServerLAN

Edge FA

WAAS FA Data Export

FA Export and/or Direct Monitoring (for example, SPAN)

Cisco NAM complements the monitoring and troubleshooting capabilities available from the WAAS Central Manager

and WAAS device command-line interface (CLI). NAM adds to the WAAS capabilities through response time

analysis for TCP flows, long-term historical reports on top-N flows, as well as detailed packet analysis. Cisco NAM

can help in detecting problems proactively and collecting information for troubleshooting before the problem

manifests as user complaints, as well as in reactive situations for problem isolation, information gathering, and

troubleshooting. Key use cases for ongoing performance monitoring and troubleshooting in a WAN optimized

network using NAM’s traffic analysis, intelligent application performance, packet capture, and historical reporting

capabilities will be highlighted in the following sections.

Use Case 1: NAM for Accelerating Problem Isolation

Let us consider the case where a remote user is complaining about slow response time in accessing data center

resources. Having a clear problem definition will assist in pinpointing the issue quickly. The following questions can

help collect information that is useful in troubleshooting an application response time issue:

1. Is this problem related to a specific application or to all the applications being used (for example, is email access

the problem or are other applications affected as well)?

2. Is the problem isolated to the user, or are others in the same site experiencing the same problems?

3. Is the service unavailable, or is it slower than earlier?

4. Since when has the problem persisted?

5. What is the IP address of the client PC and the server resource involved in the problem?

6. What is the traffic mix at the remote branch?

Cisco NAM’s real-time and historical traffic analysis and response time analysis capabilities can help shed more light

on the information collected through the preceding questions.

Real-time response statistics from the WAE client data source filtered by the client IP address as shown in Figure 2

will provide insights into all the applications the client is accessing and the response time per application. This can

be used to answer the first question: Is this problem related to a specific application or to all the applications being

used? Similarly, filtering on applications will provide insights into the response time for the same application as

experienced by various clients at the same site. This can be used to answer the second question: Is the problem

isolated to the user, or are others in the same site experiencing the same problems?