# Network Input Plugin

This plugin gathers metrics about network interface and protocol usage.

⭐ Telegraf v0.1.1
🏷️ network
💻 all

## Global configuration options <!-- @/docs/includes/plugin_config.md -->

Plugins support additional global and plugin configuration settings for tasks
such as modifying metrics, tags, and fields, creating aliases, and configuring
plugin ordering. See [CONFIGURATION.md][CONFIGURATION.md] for more details.

[CONFIGURATION.md]: ../../../docs/CONFIGURATION.md#plugins

## Configuration

```toml @sample.conf
# Gather metrics about network interfaces
[[inputs.net]]
  ## By default, telegraf gathers stats from any up interface (excluding loopback)
  ## Setting interfaces will tell it to gather these explicit interfaces,
  ## regardless of status. When specifying an interface, glob-style
  ## patterns are also supported.
  # interfaces = ["eth*", "enp0s[0-1]", "lo"]
```

## Metrics

The fields from this plugin are gathered in the _net_ measurement.

Fields (all platforms):

* bytes_sent - The total number of bytes sent by the interface
* bytes_recv - The total number of bytes received by the interface
* packets_sent - The total number of packets sent by the interface
* packets_recv - The total number of packets received by the interface
* err_in - The total number of receive errors detected by the interface
* err_out - The total number of transmit errors detected by the interface
* drop_in - The total number of received packets dropped by the interface
* drop_out - The total number of transmitted packets dropped by the interface
* speed - The interface's latest or current speed value, in Mbits/sec. May be
          -1 if unsupported by the interface

Different platforms gather the data above with different mechanisms. Telegraf
uses the ([gopsutil](https://github.com/shirou/gopsutil)) package, which under
Linux reads the /proc/net/dev file.  Under freebsd/openbsd and darwin the plugin
uses netstat.

Additionally, for the time being _only under Linux_, the plugin gathers system
wide stats for different network protocols using /proc/net/snmp (tcp, udp, icmp,
etc.).  Explanation of the different metrics exposed by snmp is out of the scope
of this document. The best way to find information would be tracing the
constants in the [Linux kernel source][source] and their usage. If
/proc/net/snmp cannot be read for some reason, telegraf ignores the error
silently.

[source]: https://elixir.bootlin.com/linux/latest/source/net/ipv4/proc.c

Tags:

* Net measurements have the following tags:
  * interface (the interface from which metrics are gathered)

Under Linux the system wide protocol metrics have the interface=all tag.

## Example Output

All platforms provide metrics like the following:

```text
net,interface=eth0,host=HOST bytes_sent=451838509i,bytes_recv=3284081640i,packets_sent=2663590i,packets_recv=3585442i,err_in=0i,err_out=0i,drop_in=4i,drop_out=0i 1492834180000000000
```

On Linux additional metrics might be provided:

```text
net,interface=eth0,host=HOST bytes_sent=451838509i,bytes_recv=3284081640i,packets_sent=2663590i,packets_recv=3585442i,err_in=0i,err_out=0i,drop_in=4i,drop_out=0i 1492834180000000000
net,interface=all,host=HOST ip_reasmfails=0i,icmp_insrcquenchs=0i,icmp_outtimestamps=0i,ip_inhdrerrors=0i,ip_inunknownprotos=0i,icmp_intimeexcds=10i,icmp_outaddrmasks=0i,icmp_indestunreachs=11005i,icmpmsg_outtype0=6i,tcp_retranssegs=14669i,udplite_outdatagrams=0i,ip_reasmtimeout=0i,ip_outnoroutes=2577i,ip_inaddrerrors=186i,icmp_outaddrmaskreps=0i,tcp_incsumerrors=0i,tcp_activeopens=55965i,ip_reasmoks=0i,icmp_inechos=6i,icmp_outdestunreachs=9417i,ip_reasmreqds=0i,icmp_outtimestampreps=0i,tcp_rtoalgorithm=1i,icmpmsg_intype3=11005i,icmpmsg_outtype69=129i,tcp_outsegs=2777459i,udplite_rcvbuferrors=0i,ip_fragoks=0i,icmp_inmsgs=13398i,icmp_outerrors=0i,tcp_outrsts=14951i,udplite_noports=0i,icmp_outmsgs=11517i,icmp_outechoreps=6i,icmpmsg_intype11=10i,icmp_inparmprobs=0i,ip_forwdatagrams=0i,icmp_inechoreps=1909i,icmp_outredirects=0i,icmp_intimestampreps=0i,icmpmsg_intype5=468i,tcp_rtomax=120000i,tcp_maxconn=-1i,ip_fragcreates=0i,ip_fragfails=0i,icmp_inredirects=468i,icmp_outtimeexcds=0i,icmp_outechos=1965i,icmp_inaddrmasks=0i,tcp_inerrs=389i,tcp_rtomin=200i,ip_defaultttl=64i,ip_outrequests=3366408i,ip_forwarding=2i,udp_incsumerrors=0i,udp_indatagrams=522136i,udplite_incsumerrors=0i,ip_outdiscards=871i,icmp_inerrors=958i,icmp_outsrcquenchs=0i,icmpmsg_intype0=1909i,tcp_insegs=3580226i,udp_outdatagrams=577265i,udp_rcvbuferrors=0i,udplite_sndbuferrors=0i,icmp_incsumerrors=0i,icmp_outparmprobs=0i,icmpmsg_outtype3=9417i,tcp_attemptfails=2652i,udplite_inerrors=0i,udplite_indatagrams=0i,ip_inreceives=4172969i,icmpmsg_outtype8=1965i,tcp_currestab=59i,udp_noports=5961i,ip_indelivers=4099279i,ip_indiscards=0i,tcp_estabresets=5818i,udp_sndbuferrors=3i,icmp_intimestamps=0i,icmpmsg_intype8=6i,udp_inerrors=0i,icmp_inaddrmaskreps=0i,tcp_passiveopens=452i 1492831540000000000
```
