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-ids.org/download.
Capstats’s git repository is located at git://git.bro-ids.org/capstats.git. You can browse the repository here.
This document describes capstats 0.16. 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 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. 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.
