ISC Bind (RNDC)

Plugin: python.d.plugin Module: bind_rndc

Overview

Monitor ISCBind (RNDC) performance for optimal DNS server operations. Monitor query rates, response times, and error rates to ensure reliable DNS service delivery.

This collector uses the rndc tool to dump (named.stats) statistics then read them to gather Bind Name Server summary performance metrics.

This collector is supported on all platforms.

This collector only supports collecting metrics from a single instance of this integration.

Default Behavior

Auto-Detection

If no configuration is given, the collector will attempt to read named.stats file at /var/log/bind/named.stats

Limits

The default configuration for this integration does not impose any limits on data collection.

Performance Impact

The default configuration for this integration is not expected to impose a significant performance impact on the system.

Metrics

Metrics grouped by scope.

The scope defines the instance that the metric belongs to. An instance is uniquely identified by a set of labels.

Per ISC Bind (RNDC) instance

These metrics refer to the entire monitored application.

This scope has no labels.

Metrics:

Metric	Dimensions	Unit
bind_rndc.name_server_statistics	requests, rejected_queries, success, failure, responses, duplicate, recursion, nxrrset, nxdomain, non_auth_answer, auth_answer, dropped_queries	stats
bind_rndc.incoming_queries	a dimension per incoming query type	queries
bind_rndc.outgoing_queries	a dimension per outgoing query type	queries
bind_rndc.stats_size	stats_size	MiB

Alerts

The following alerts are available:

Alert name	On metric	Description
bind_rndc_stats_file_size	bind_rndc.stats_size	BIND statistics-file size

Setup

Prerequisites

Minimum bind version and permissions

Version of bind must be >=9.6 and the Netdata user must have permissions to run rndc stats

Setup log rotate for bind stats

BIND appends logs at EVERY RUN. It is NOT RECOMMENDED to set update_every below 30 sec. It is STRONGLY RECOMMENDED to create a bind-rndc.conf file for logrotate.

To set up BIND to dump stats do the following:

1. Add to 'named.conf.options' options {}: statistics-file "/var/log/bind/named.stats";

2. Create bind/ directory in /var/log: cd /var/log/ && mkdir bind

3. Change owner of directory to 'bind' user: chown bind bind/

4. RELOAD (NOT restart) BIND: systemctl reload bind9.service

5. Run as a root 'rndc stats' to dump (BIND will create named.stats in new directory)

To allow Netdata to run 'rndc stats' change '/etc/bind/rndc.key' group to netdata: chown :netdata rndc.key

Last, BUT NOT least, is to create bind-rndc.conf in logrotate.d/:

/var/log/bind/named.stats {

    daily
    rotate 4
    compress
    delaycompress
    create 0644 bind bind
    missingok
    postrotate
        rndc reload > /dev/null
    endscript
}

To test your logrotate conf file run as root: logrotate /etc/logrotate.d/bind-rndc -d (debug dry-run mode)

Configuration

File

The configuration file name for this integration is python.d/bind_rndc.conf.

You can edit the configuration file using the edit-config script from the Netdata config directory.

cd /etc/netdata 2>/dev/null || cd /opt/netdata/etc/netdata
sudo ./edit-config python.d/bind_rndc.conf

Options

There are 2 sections:

• Global variables
• One or more JOBS that can define multiple different instances to monitor.

The following options can be defined globally: priority, penalty, autodetection_retry, update_every, but can also be defined per JOB to override the global values.

Additionally, the following collapsed table contains all the options that can be configured inside a JOB definition.

Every configuration JOB starts with a job_name value which will appear in the dashboard, unless a name parameter is specified.

Config options

Name	Description	Default	Required
update_every	Sets the default data collection frequency.	5	no
priority	Controls the order of charts at the netdata dashboard.	60000	no
autodetection_retry	Sets the job re-check interval in seconds.	0	no
penalty	Indicates whether to apply penalty to update_every in case of failures.	yes	no
name	Job name. This value will overwrite the job_name value. JOBS with the same name are mutually exclusive. Only one of them will be allowed running at any time. This allows autodetection to try several alternatives and pick the one that works.		no
named_stats_path	Path to the named stats, after being dumped by nrdc	/var/log/bind/named.stats	no

Examples

Local bind stats

Define a local path to bind stats file

local:
 named_stats_path: '/var/log/bind/named.stats'

Troubleshooting

Debug Mode

To troubleshoot issues with the bind_rndc collector, run the python.d.plugin with the debug option enabled. The output should give you clues as to why the collector isn't working.

• Navigate to the plugins.d directory, usually at /usr/libexec/netdata/plugins.d/. If that's not the case on your system, open netdata.conf and look for the plugins setting under [directories].

  cd /usr/libexec/netdata/plugins.d/

• Switch to the netdata user.

  sudo -u netdata -s

• Run the python.d.plugin to debug the collector:

  ./python.d.plugin bind_rndc debug trace