To create a custom log configuration in AEM, the developer should create an OSGi configuration file for the org.apache.sling.commons.log.LogManager.factory.writer component. This configuration file should be placed under the appropriate runmode-specific folder within the config directory.

Here is the detailed process:

Create Configuration File:

Create a new XML file named org.apache.sling.commons.log.LogManager.factory.writer-.xml in the config. folder.

The can be any unique identifier for your custom log configuration.

Specify Configuration:

Add the necessary configuration properties within this XML file. For example:

xmlns:jcr="http://www.jcp.org/jcr/1.0"

jcr:primaryType="sling:OsgiConfig"

org.apache.sling.commons.log.file="/var/log/custom.log"

org.apache.sling.commons.log.level="debug"

org.apache.sling.commons.log.pattern="\{0\}"

org.apache.sling.commons.log.names="[com.myproject.custom]" />

Deploy Configuration:

Save the configuration file and deploy it to the appropriate environment. The logging system in AEM will pick up this configuration and create a custom log file with the specified settings.

References:

Adobe Experience Manager Logging

Apache Sling Logging