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.\" 24.\" $FreeBSD$ 25.Dd October 7, 2021 26.Dt PROMETHEUS_SYSCTL_EXPORTER 8 27.Os 28.Sh NAME 29.Nm prometheus_sysctl_exporter 30.Nd print kernel state as Prometheus metrics 31.Sh SYNOPSIS 32.Nm prometheus_sysctl_exporter 33.Op Fl dgh 34.Op Fl e Ar pattern 35.Op Fl i Ar pattern 36.Op Ar prefix ... 37.Sh DESCRIPTION 38Prometheus is a monitoring system that gathers metrics from its targets 39by fetching them through HTTP GET requests. 40Metrics are identified by a name and an optional set of labels. 41Sample values are required to be numerical. 42.Pp 43The 44.Nm 45utility prints the values of sysctl nodes to standard output, 46formatted such that they can be scraped by Prometheus directly. 47By default, 48it prints metrics for all numerically representable nodes in the sysctl 49namespace. 50It is also possible to limit output to a smaller number of metrics by 51specifying one or more prefixes as arguments. 52.Pp 53Metrics printed by this utility are named 54.Ql sysctl_ , 55followed by the name of the sysctl node having its 56.Ql .\& 57separators replaced by 58.Ql _ . 59Components on which it is desirable to aggregate (e.g., 60names of devices) are omitted from the metric's name, 61but are appended as labels instead. 62.Pp 63There are two different methods for exporting the output of 64.Nm 65to Prometheus. 66The first method is to periodically invoke this utility through 67.Xr cron 8 68and store its output in a textfile. 69The metrics in this textfile can then be served over HTTP using the 70Prometheus node exporter's textfile collector. 71The second method is to run this utility through 72.Xr inetd 8 . 73TCP port 9124 has been allocated for this purpose. 74.Pp 75The following options are available: 76.Bl -tag -width indent 77.It Fl d 78Print descriptions of metrics when available. 79.It Fl e Ar pattern 80Same as 81.Fl i , 82except exclude metrics that match 83.Ar pattern . 84.It Fl g 85Gzip compresses the HTTP response body. 86.It Fl h 87Precede the output with a HTTP response header. 88This flag is required when running this utility through 89.Xr inetd 8 . 90.It Fl i Ar pattern 91If specified, include metrics that match 92.Ar pattern . 93The format of 94.Ar pattern 95is to be a regular expression as described in 96.Xr re_format 7 . 97The provided regular expression is tested against the Prometheus 98metric name. 99.El 100.Sh SEE ALSO 101.Xr cron 8 , 102.Xr inetd 8 , 103.Xr sysctl 8 , 104.Xr SYSCTL_ADD_NODE_WITH_LABEL 9 105.Pp 106Prometheus project: 107.Pa https://prometheus.io/ . 108.Pp 109Prometheus exposition formats: 110.Pa https://prometheus.io/docs/instrumenting/exposition_formats/ . 111.Pp 112Prometheus node exporter: 113.Pa https://github.com/prometheus/node_exporter . 114.Pp 115Prometheus default port allocations: 116.Pa https://github.com/prometheus/prometheus/wiki/Default-port-allocations . 117.Sh HISTORY 118.Nm 119first appeared in 120.Fx 12.0 . 121.Sh AUTHORS 122.An Nuxi : Pa https://nuxi.nl/ . 123