Reordered according to my intuition.
On busy systems vebose logging can produce several MB of logs per
second and will slow down operation.
+It is also possible to obtain verbose logs for *a single request*, see chapter :ref:`mod-http-trace`.
+
Less verbose logging for DNSSEC validation errors can be enabled using :ref:`mod-bogus_log` module.
Various statistics for monitoring purposes are available in :ref:`mod-stats` module, including export to central systems like Graphite, Metronome, InfluxDB, or Prometheus format.
Resolver :ref:`mod-watchdog` is tool to detect and recover from potential bugs that cause the resolver to stop responding properly to queries.
-If none of these options fits your deployment or if you have special needs you can configure your own checks and exports using :ref:`async-events`.
+Additional monitoring and debugging methods are described below. If none of these options fits your deployment or if you have special needs you can configure your own checks and exports using :ref:`async-events`.
.. toctree::
:maxdepth: 1
- modules-nsid
- modules-stats
- modules-dnstap
- modules-watchdog
modules-bogus_log
+ modules-stats
+ modules-nsid
modules-http-trace
+ modules-watchdog
+ modules-dnstap
modules-ta_sentinel
modules-ta_signal_query
modules-detect_time_skew
.. _mod-dnstap:
-Dnstap
-======
+Dnstap (traffic collection)
+===========================
The ``dnstap`` module supports logging DNS responses to a unix socket
-in dnstap_ format using fstrm framing library.
+in `dnstap format <https://dnstap.info>`_ using fstrm framing library.
This logging is useful if you need effectivelly log all DNS traffic.
The unix socket and the socket reader must be present before starting resolver instances.
.. _mod-http-trace:
-Tracing requests
-================
+Debugging a single request
+==========================
The `HTTP module <mod-http>`_ provides ``/trace`` endpoint which allows to trace various
aspects of the request execution. The basic mode allows you to resolve a query
-and trace verbose logs (and messages received):
+and trace verbose logs for it (and messages received):
.. code-block:: bash
[ 8138] [iter] <= rcode: NOERROR
[ 8138] [resl] finished: 4, queries: 1, mempool: 81952 B
-See chapter about `HTTP module <mod-http>`_ for further instructions how to load HTTP module.
+See chapter about `HTTP module <mod-http>`_ for further instructions how to load ``webmgmt``
+endpoint into HTTP module, it is a prerequisite for using ``/trace``.