How to configure the PostgreSQL database
Warning: The feature is currently available in the channel 14/edge only (revision 160+) and will be released to the channel 14/stable soon.
To configure the PostgreSQL database you need to:
To configure a new value for a PostgreSQL parameter you can simply change the value of a config option:
juju config postgresql-k8s `<parameter_group_in_lowercase>_<postgresql_parameter_in_lowercase>`=<value>
As an example:
juju config postgresql-k8s response_lc_monetary=en_GB.utf8
Note: the parameter groups for each PostgreSQL parameter are used to better organise them and are listed at Supported database configurations/parameters.
After changing the value of one or more of the parameters, the PostgreSQL charm will apply the new configuration to the database.
If some parameters need a database restart (i.e. shared_buffers), the charm will automatically restart the database to apply the new configuration.
In that situation, you can check the restart operation status of each unit like in the following example (from juju status):
Model Controller Cloud/Region Version SLA Timestamp
dev micro microk8s/localhost 3.1.6 unsupported 19:44:02Z
App Version Status Scale Charm Channel Rev Address Exposed Message
postgresql-k8s 14.9 waiting 3 postgresql-k8s 0 10.152.183.142 no installing agent
Unit Workload Agent Address Ports Message
postgresql-k8s/0 maintenance executing 10.1.123.45 Executing restart operation
postgresql-k8s/1* active executing 10.1.123.46
postgresql-k8s/2 waiting executing 10.1.123.48 Awaiting restart operation
If any parameter is configured with an invalid value, the charm will get into an error state,
Also, in the Juju debug logs you can see why the configuration change failed:
1 validation error for CharmConfig durability_synchronous_commit
Value not one of 'on', 'remote_apply' or 'remote_write'
To resolve that, call one of the following commands:
juju config postgresql-k8s --reset <config_option_name> # reset to the default value of the config option
juju config postgresql-k8s <config_option_name>=<valid_value> # set a valid value for the config option
Then call:
juju resolve postgresql-k8s/0
Not all PostgreSQL parameters are available to configure through the charm to avoid combinations of settings that can impact the database usage or performance. The list of supported parameters is available at Supported database configurations/parameters.
Values for each config option related to a PostgreSQL parameter can be checked on PostgreSQL K8S charm config options.