Adding upstream version 1.34.4.

Signed-off-by: Daniel Baumann <daniel@debian.org>

plugins/inputs/openntpd/README.md

@@ -0,0 +1,106 @@
+# OpenNTPD Input Plugin
+
+Get standard NTP query metrics from [OpenNTPD][] using the ntpctl command.
+
+[OpenNTPD]: http://www.openntpd.org/
+
+Below is the documentation of the various headers returned from the NTP query
+command when running `ntpctl -s peers`.
+
+- remote – The remote peer or server being synced to.
+- wt – the peer weight
+- tl – the peer trust level
+- st (stratum) – The remote peer or server Stratum
+- next – number of seconds until the next poll
+- poll – polling interval in seconds
+- delay – Round trip communication delay to the remote peer
+or server (milliseconds);
+- offset – Mean offset (phase) in the times reported between this local host and
+the remote peer or server (RMS, milliseconds);
+- jitter – Mean deviation (jitter) in the time reported for that remote peer or
+server (RMS of difference of multiple time samples, milliseconds);
+
+## Global configuration options <!-- @/docs/includes/plugin_config.md -->
+
+In addition to the plugin-specific configuration settings, plugins support
+additional global and plugin configuration settings. These settings are used to
+modify metrics, tags, and field or create aliases and configure ordering, etc.
+See the [CONFIGURATION.md][CONFIGURATION.md] for more details.
+
+[CONFIGURATION.md]: ../../../docs/CONFIGURATION.md#plugins
+
+## Configuration
+
+```toml @sample.conf
+# Get standard NTP query metrics from OpenNTPD.
+[[inputs.openntpd]]
+  ## Run ntpctl binary with sudo.
+  # use_sudo = false
+
+  ## Location of the ntpctl binary.
+  # binary = "/usr/sbin/ntpctl"
+
+  ## Maximum time the ntpctl binary is allowed to run.
+  # timeout = "5s"
+```
+
+## Metrics
+
+- ntpctl
+  - tags:
+    - remote
+    - stratum
+  - fields:
+    - delay (float, milliseconds)
+    - jitter (float, milliseconds)
+    - offset (float, milliseconds)
+    - poll (int, seconds)
+    - next (int, seconds)
+    - wt (int)
+    - tl (int)
+
+## Permissions
+
+It's important to note that this plugin references ntpctl, which may require
+additional permissions to execute successfully.
+Depending on the user/group permissions of the telegraf user executing this
+plugin, you may need to alter the group membership, set facls, or use sudo.
+
+**Group membership (Recommended)**:
+
+```bash
+$ groups telegraf
+telegraf : telegraf
+
+$ usermod -a -G ntpd telegraf
+
+$ groups telegraf
+telegraf : telegraf ntpd
+```
+
+**Sudo privileges**:
+If you use this method, you will need the following in your telegraf config:
+
+```toml
+[[inputs.openntpd]]
+  use_sudo = true
+```
+
+You will also need to update your sudoers file:
+
+```bash
+$ visudo
+# Add the following lines:
+Cmnd_Alias NTPCTL = /usr/sbin/ntpctl
+telegraf ALL=(ALL) NOPASSWD: NTPCTL
+Defaults!NTPCTL !logfile, !syslog, !pam_session
+```
+
+Please use the solution you see as most appropriate.
+
+## Example Output
+
+```text
+openntpd,remote=194.57.169.1,stratum=2,host=localhost tl=10i,poll=1007i,
+offset=2.295,jitter=3.896,delay=53.766,next=266i,wt=1i 1514454299000000000
+```