Download SPV - User Guide Documentation

SPV - User Guide Documentation, Release 2.9
• number of timeouts
• number of RSTs from client
• number of RSTs from server
• number of FINs from client
• number of FINs from server
5.7 Packet level analysis
5.7.1 Objectives
Once you have identified the origin of an issue, you may want to analyze it further by looking at the packets
themselves. You have two ways to realize this:
• Manual capture through Pulsar’s tcpdump command
• Automatic packet capture
5.7.2 Manual packet capture
By connecting through Pulsar, you can start a manual capture of any traffic viewed on the interface of your device.
To do so, you need to go through 3 steps:
1. Connect to Pulsar (see Pulsar (page 26))
2. Enter the command to launch the trace:
<host_ip>.
for example, tcpdump -i <interface> host
3. Enter Control+C to stop the trace.
Note:
• you can access a help by entering help tcpdump.
• you can refer to tcpdump command (http://www.tcpdump.org). Please, have a look at the online manual
(http://www.tcpdump.org/tcpdump_man.html).
• all parameters are availiable except the -w.
Accessing the tracefile
You will not be able to view the trace through Pulsar; to access the PCAP file, you should connect to the probe via
FTP, using a FTP client and the Pulsar admin user (see Pulsar (page 26)).
5.7.3 Automated packet capture (“AutoPCAP”)
Principles
Performance Vision can capture packets automatically, in case abnormal values are observed on critical servers.
These packets are presented for later analysis as PCAP files, which can be downloaded through the web graphical
interface at the conversation level.
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Chapter 5. Interpreting the results