Time and time again, I hear people telling me how vital OPNET analysis is for their applications. Whether you’re moving or consolidating a data center, deploying a new product, or simply debugging an issue with an existing problem, the detailed information that OPNET products can provide can be critical to your success.
The problem is that the OPNET products can be time consuming, the data can be overwhelming, and the skill level required to generate and understand the data often requires dedicated people for. One solution is to use Shunra’s VE Desktop Professional to speed-up the OPNET process.
Here is how:
Typical problem: Two data centers that housed the online store servers were just consolidated into one data center. Now customers are complaining that the site is loading “slowly” and their shopping carts keep emptying without reason.
Process:
1) Find out where the problems are being reported and pick the highest priority (or worst network connection).
2) Understand what the network conditions are from that location to the data center.
a. A lot of products exist that can help you understand what your latency, packet loss, and available bandwidth are. For your first pass, rough numbers will often be good enough to identify the problem (e.g. Ping for latency and packet loss, FTP for available bandwidth).
3) Use VE Desktop to emulate the network between the problem location and the data center in your lab.
a. Use the rough network numbers to start with
b. Turn on packet capture
c. Time some of the transactions that users have been complaining about
4) If you can recreate the symptoms already, and it’s likely you can, then you can move on from here. If you can’t then you can deploy the VE Desktop to one of the problem areas, run it with packet capture on and no emulation, and have the end user execute some of the problem transactions while timing them with VE Desktop.
5) The results of either #3 or #4 that are of interest are the packet capture and the transaction timing results. With this data Shunra’s VE Analyzer can correlate the transaction timing with the captured packets. VE Analyzer will then provide a summary analysis of the transactions. In many cases, this will identify the high level problem and give you a focused area to debug further. If it doesn’t, then VE Analyzer will also tell you which frames within the packet capture correlate with the beginning and end of each transaction.
6) Armed with a packet capture and your frame numbers for each transaction, you can quickly use any packet sniffer on the market to isolate the packets for only the transactions you wish to analyze further in OPNET. The ability to use VE Desktop and VE Analyzer to get this information will save you hours…
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