pktstat understands the following command line options:
If the terminal supports it, the display briefly highlights in bold new connections or old connections carrying data after a period of inactivity.
Simple statistics about the interface are also displayed such as the current and average bit rates (measured just above the data link layer). Load averages refer to bit rate decayed averages for the last 1, 5 and 15 minutes.
During display, the following keystrokes are recognised:
All packet classes, or flows, are Qq tagged with a descriptive string, such as `tcp' ftpserver:20524 <-> cathexis:17771 .
In addition to being tagged, some protocol-state information can be associated with a flow. This is displayed immediately below a flow line. Descriptive information for FTP, HTTP, X11 and SUP connections is determined from simple decoding of some packets. If the connection is 'open', it is introduced with a right angle shape (+), otherwise it is introduced with a hyphen character.
tcp www:80 <-> hamartia:19179 + GET /index.html
Abbreviation patterns are a way of further combining flows. As packets are decoded, their flow name is constructed at the various protocol layers. At address combining stage (where arrows such as `->' are inserted) and at the final display stage, flow names are checked against a list of abbreviation patterns, and the abbreviation's name substituted if a match is found. For example, the pattern `*' <-> *:domain will match DNS packets in both the UDP and TCP layers.
Abbreviations take the form [abbrev @ pattern ] The pattern part can contain the wildcard character, asterisk `*' which matches zero or more non-space characters. The space character matches one or more whitespace characters. Leading and trailing spaces are ignored.
If the optional abbrev is not specified, the the pattern text itself is used as the abbreviation.
Patterns are checked in the order given on the command line or in the files, i.e. as soon as one of the patterns matches a tag, no further patterns are considered. Recall that patterns can be applied multiple times to a tag.
A patterns file can contain blank lines, which are ignored. Comment lines that commence with a `#' character are also ignored.
After processing all command line abbreviations and abbreviation files, pktstat looks for and loads the files .pktstatrc $HOME/.pktstatrc and /etc/pktstatrc This behaviour is suppressed by supplying an -A none option.
Here are the contents of my .pktstatrc file:
dns @ udp *:domain <-> * dns @ udp * <-> *:domain irc @ udp 192.168.0.81:6666 <-> *
DNS lookups can take too much time, possibly leading to missed packets.
The data rates do not take into account data link framing overhead or compression savings at the data link layer.
The direction of traffic is not taken into account: both ingress and egress data rates are combined. If you want to separate them, you will need to use a filter expression.
Descriptive information for X11, FTP, HTTP and SUP flows is derived from the very first packets sent on those protocols. If you start pktstat after any of these flows have commenced, there may be no description available for them.