Using Netmaster Smarttrace to record TCP 3-way handshake
Article ID: 107167
CMDB for z/OSNetSpy Network PerformanceNetMaster Network AutomationSOLVENetMaster Network Management for SNANetMaster Network Management for TCP/IPNetMaster File Transfer Management
How can a the Smarttrace filter be defined to just record the three-way TCP handshake packets? It is sometimes needed when trying to capture the handshake from a particular IP on a a busy port lots of connections from many locations with lots of traffic flow, ie FTP or Telnet.
Release: SLOPFC00200-12.1-NetMaster-File Transfer Management Component:
The closest Netmaster can come is 13 packets per connection, as described below:
To create the SmartTrace definition, go to /SMART Add a new smarttrace definition Select New Multiple TCP Connection Trace
Put in the port (and stack if you want) then PF8 to the last screen.
Define the Trace Limit and Initial Packets Traced fields as below. The rest are whatever best fit your requirements. Trace Limit ............... 10 <----------- minimum number you can have Stop At Limit? ............ NO Trace Expiry .............. 1:00 Initial Packets Traced .... 3 <--------------- keeps the 3-way handshake Maximum Connections Traced 100
This results in keeping the 3-way handshake plus 10 packets. As stated in the online doc, 10 is the lowest Trace Limit allowed.
Attempts at setting the trace limit to 0 cause it to be reset to 250.