From ef32ba704ddc08da31c49ca1421d05ab64cd3972 Mon Sep 17 00:00:00 2001 From: Kefu Chai Date: Thu, 19 Sep 2024 14:44:48 +0800 Subject: [PATCH] docs: explain precedence of configure options to explain for instance which setting takes effect if both command line options and `scylla.yaml` configures the same parameter. Signed-off-by: Kefu Chai (cherry picked from commit 1aa030a8cd3ec0768b3e3e96a41bece8b71bfcc0) Closes scylladb/scylladb#20775 --- docs/reference/configuration-parameters.rst | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/docs/reference/configuration-parameters.rst b/docs/reference/configuration-parameters.rst index 40dbbc402a..9486dcac9d 100644 --- a/docs/reference/configuration-parameters.rst +++ b/docs/reference/configuration-parameters.rst @@ -3,7 +3,23 @@ Configuration Parameters ======================== This section contains a list of properties that can be configured in ``scylla.yaml`` - the main configuration file for ScyllaDB. -In addition, properties that support live updates (liveness) can be updated via the ``system.config`` virtual table or the REST API. +In addition, properties that support live updates (liveness) can be updated via the ``system.config`` virtual table or the :doc:`REST API `. + +Live update means that parameters can be modified dynamically while the server +is running. If ``liveness`` of a parameter is set to ``true``, sending the ``SIGHUP`` +signal to the server processes will trigger ScyllaDB to re-read its configuration +and override the current configuration with the new value. + +**Configuration Precedence** + +As the parameters can be configured in more than one place, ScyllaDB applies them +in the following order with ``scylla.yaml`` parameters updated via ``SIGHUP`` +having the highest priority: + +#. Live update via ``scylla.yaml`` (with ``SIGHUP``) or REST API +#. ``system.config`` table +#. command line options +#. ``scylla.yaml`` .. scylladb_config_list:: ../../db/config.hh ../../db/config.cc :template: db_config.tmpl