capstats - A tool to get some NIC statistics.

capstats is a small tool to collect statistics on the current load of a network interface, using either libpcap or the native interface for Endace’s. It reports statistics per time interval and/or for the tool’s total run-time.

Download

You can find the latest capstats release for download at http://www.bro.org/download.

Capstats’s git repository is located at git://git.bro.org/capstats.git. You can browse the repository here.

This document describes capstats 0.25. See the CHANGES file for version history.

Output

Here’s an example output with output in one-second intervals until CTRL-C is hit:

>capstats -i nve0 -I 1
1186620936.890567 pkts=12747 kpps=12.6 kbytes=10807 mbps=87.5 nic_pkts=12822 nic_drops=0 u=960 t=11705 i=58 o=24 nonip=0
1186620937.901490 pkts=13558 kpps=13.4 kbytes=11329 mbps=91.8 nic_pkts=13613 nic_drops=0 u=1795 t=24339 i=119 o=52 nonip=0
1186620938.912399 pkts=14771 kpps=14.6 kbytes=13659 mbps=110.7 nic_pkts=14781 nic_drops=0 u=2626 t=38154 i=185 o=111 nonip=0
1186620939.012446 pkts=1332 kpps=13.3 kbytes=1129 mbps=92.6 nic_pkts=1367 nic_drops=0 u=2715 t=39387 i=194 o=112 nonip=0
=== Total
1186620939.012483 pkts=42408 kpps=13.5 kbytes=36925 mbps=96.5 nic_pkts=1 nic_drops=0 u=2715 t=39387 i=194 o=112 nonip=0

Each line starts with a timestamp and the other fields are:

pkts:Absolute number of packets seen by capstats during interval. kpps:Number of thousands of packets per second. kbytes:Absolute number of KBytes during interval. mbps:Mbits/sec. nic_pkts:Number of packets as reported by libpcap’s pcap_stats() (may not match pkts) nic_drops:Number of packet drops as reported by libpcap’s pcap_stats(). u:Number of UDP packets. t:Number of TCP packets. i:Number of ICMP packets. o:Number of IP packets with protocol other than TCP, UDP, and ICMP. nonip:Number of non-IP packets.

Options

A list of all options:

capstats [Options] -i interface

   -i| --interface <interface>    Listen on interface
   -d| --dag                      Use native DAG API
   -f| --filter <filter>          BPF filter
   -I| --interval <secs>          Stats logging interval
   -l| --syslog                   Use syslog rather than print to stderr
   -n| --number <count>           Stop after outputting <number> intervals
   -N| --select                   Use select() for live pcap (for testing only)
   -p| --payload <n>              Verifies that packets' payloads consist
                                  entirely of bytes of the given value.
   -q| --quiet <count>            Suppress output, exit code indicates >= count
                                  packets received.
   -S| --size <size>              Verify packets to have given <size>
   -s| --snaplen <size>           Use pcap snaplen <size>
   -v| --version                  Print version and exit
   -w| --write <filename>         Write packets to file

Installation

capstats has been tested on Linux, FreeBSD, and MacOS. Please see the INSTALL file for installation instructions.