1.\" Copyright (c) 2016 Nuxi, https://nuxi.nl/ 2.\" 3.\" Redistribution and use in source and binary forms, with or without 4.\" modification, are permitted provided that the following conditions 5.\" are met: 6.\" 1. Redistributions of source code must retain the above copyright 7.\" notice, this list of conditions and the following disclaimer. 8.\" 2. Redistributions in binary form must reproduce the above copyright 9.\" notice, this list of conditions and the following disclaimer in the 10.\" documentation and/or other materials provided with the distribution. 11.\" 12.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 13.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 14.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 15.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 16.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 17.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 18.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 19.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 20.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 21.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 22.\" SUCH DAMAGE. 23.Dd October 7, 2021 24.Dt PROMETHEUS_SYSCTL_EXPORTER 8 25.Os 26.Sh NAME 27.Nm prometheus_sysctl_exporter 28.Nd print kernel state as Prometheus metrics 29.Sh SYNOPSIS 30.Nm prometheus_sysctl_exporter 31.Op Fl dgh 32.Op Fl e Ar pattern 33.Op Fl i Ar pattern 34.Op Ar prefix ... 35.Sh DESCRIPTION 36Prometheus is a monitoring system that gathers metrics from its targets 37by fetching them through HTTP GET requests. 38Metrics are identified by a name and an optional set of labels. 39Sample values are required to be numerical. 40.Pp 41The 42.Nm 43utility prints the values of sysctl nodes to standard output, 44formatted such that they can be scraped by Prometheus directly. 45By default, 46it prints metrics for all numerically representable nodes in the sysctl 47namespace. 48It is also possible to limit output to a smaller number of metrics by 49specifying one or more prefixes as arguments. 50.Pp 51Metrics printed by this utility are named 52.Ql sysctl_ , 53followed by the name of the sysctl node having its 54.Ql .\& 55separators replaced by 56.Ql _ . 57Components on which it is desirable to aggregate (e.g., 58names of devices) are omitted from the metric's name, 59but are appended as labels instead. 60.Pp 61There are two different methods for exporting the output of 62.Nm 63to Prometheus. 64The first method is to periodically invoke this utility through 65.Xr cron 8 66and store its output in a textfile. 67The metrics in this textfile can then be served over HTTP using the 68Prometheus node exporter's textfile collector. 69The second method is to run this utility through 70.Xr inetd 8 . 71TCP port 9124 has been allocated for this purpose. 72.Pp 73The following options are available: 74.Bl -tag -width indent 75.It Fl d 76Print descriptions of metrics when available. 77.It Fl e Ar pattern 78Same as 79.Fl i , 80except exclude metrics that match 81.Ar pattern . 82.It Fl g 83Gzip compresses the HTTP response body. 84.It Fl h 85Precede the output with a HTTP response header. 86This flag is required when running this utility through 87.Xr inetd 8 . 88.It Fl i Ar pattern 89If specified, include metrics that match 90.Ar pattern . 91The format of 92.Ar pattern 93is to be a regular expression as described in 94.Xr re_format 7 . 95The provided regular expression is tested against the Prometheus 96metric name. 97.El 98.Sh SEE ALSO 99.Xr cron 8 , 100.Xr inetd 8 , 101.Xr sysctl 8 , 102.Xr SYSCTL_ADD_NODE_WITH_LABEL 9 103.Pp 104Prometheus project: 105.Pa https://prometheus.io/ . 106.Pp 107Prometheus exposition formats: 108.Pa https://prometheus.io/docs/instrumenting/exposition_formats/ . 109.Pp 110Prometheus node exporter: 111.Pa https://github.com/prometheus/node_exporter . 112.Pp 113Prometheus default port allocations: 114.Pa https://github.com/prometheus/prometheus/wiki/Default-port-allocations . 115.Sh HISTORY 116.Nm 117first appeared in 118.Fx 12.0 . 119.Sh AUTHORS 120.An Nuxi : Pa https://nuxi.nl/ . 121