It is not currently possible to specify packet tracing from the command line. This is because a global option for packet tracing would potentially create too much output. Global tracing statements have an immediate effect, especially parsing options that effect the parsing of the configuration file. Tracing values inherited by protocols specified in the configuration file are initially inherited from the global options in effect as they are parsed, unless they are overridden by more specific options. After the configuration file is read, tracing options that were not explicitly specified are inherited from the global options in effect at the end of the configuration file.
Packet tracing Tracing of packets is very flexible.
For any given protocol there are one or more options for tracing packets. Normally packets are traced in a terse form of one or two lines. When detail is specified, a more verbose format is used to provide further detail on the contents of the packet. Without these options both sent and received packets will be traced. Detail , if specified, must be before send or recv .