Problem:
When viewing logs using kubectl logs pod-name, you may notice that debug logs or entries from neo4j.log and debug.log are not appearing. This issue has been observed in Neo4j versions V4.4.

Cause:
Neo4j V4.4 does not redirect all logs to stdout by default when deployed using Helm charts, which is necessary for viewing them using Kubernetes commands like kubectl logs pod-name. By default, the logs are written to files inside the container, not output to stdout or stderr, which are the streams captured by Kubernetes logging.

Solution for V4.4:
To enable logging to stdout in Neo4j V4.4, you need to modify the values.yaml file by adding the following configuration in the config section:

config:
   dbms.logs.user.stdout_enabled: "true"

This configuration will redirect neo4j.log and debug.log to stdout, making them accessible via kubectl logs pod-name.

For more information on this setting, refer to the official Neo4j documentation:
dbms.logs.user.stdout_enabled

Solution for V5.x:
Starting from Neo4j V5.6, there is increased flexibility in configuring log outputs thanks to the introduction of Log4j configuration in values.yaml. By default, in V5 only neo4j.log is sent to stdout. You can now configure appenders directly in the server-logs.xml file, which allows all the logs to be sent to stdout and stderr without additional workarounds.

For instance, you need to add the Console Appender to your different loggers ( debug, query, http, security, ...) in server-logs.xml:
 

<Configuration monitorInterval="30" packages="org.neo4j.logging.log4j">
    <Appenders>
        <Console name="console" target="SYSTEM_OUT">
            <PatternLayout pattern="%m%n"/>
        </Console>
    </Appenders>

    <Loggers>
        <Root level="INFO">
            <AppenderRef ref="console"/>
        </Root>

        <Logger name="HttpLogger" level="INFO" additivity="false">
            <AppenderRef ref="console"/>
        </Logger>

        <Logger name="QueryLogger" level="INFO" additivity="false">
            <AppenderRef ref="console"/>
        </Logger>

        <Logger name="SecurityLogger" level="INFO" additivity="false">
            <AppenderRef ref="console"/>
        </Logger>
    </Loggers>
</Configuration>

Below is a full example on how to add the logging section to the values.yaml. In this example the debug, query, http and security logs are all added to the console appender that has a SYSTEM_OUT as a target:
 

logging:
  serverLogsXml: |-
    <?xml version="1.0" encoding="UTF-8"?>
    <!-- Example JSON logging configuration -->
    <Configuration status="ERROR" monitorInterval="30" packages="org.neo4j.logging.log4j">
        <Appenders>
        	<Console name="console" target="SYSTEM_OUT">
            	<PatternLayout pattern="%m%n"/>
        	</Console>

            <!-- Default debug.log, please keep -->
            <RollingRandomAccessFile name="DebugLog" fileName="${config:server.directories.logs}/debug.log"
                                     filePattern="$${config:server.directories.logs}/debug.log.%02i">
                <JsonTemplateLayout eventTemplateUri="classpath:org/neo4j/logging/StructuredLayoutWithMessage.json"/>
                <Policies>
                    <SizeBasedTriggeringPolicy size="20 MB"/>
                </Policies>
                <DefaultRolloverStrategy fileIndex="min" max="7"/>
            </RollingRandomAccessFile>

            <RollingRandomAccessFile name="HttpLog" fileName="${config:server.directories.logs}/http.log"
                                     filePattern="$${config:server.directories.logs}/http.log.%02i">
                <JsonTemplateLayout eventTemplateUri="classpath:org/neo4j/logging/StructuredLayoutWithMessage.json"/>
                <Policies>
                    <SizeBasedTriggeringPolicy size="20 MB"/>
                </Policies>
                <DefaultRolloverStrategy fileIndex="min" max="5"/>
            </RollingRandomAccessFile>

            <RollingRandomAccessFile name="QueryLog" fileName="${config:server.directories.logs}/query.log"
                                     filePattern="$${config:server.directories.logs}/query.log.%02i">
                <JsonTemplateLayout eventTemplateUri="classpath:org/neo4j/logging/QueryLogJsonLayout.json"/>
                <Policies>
                    <SizeBasedTriggeringPolicy size="20 MB"/>
                </Policies>
                <DefaultRolloverStrategy fileIndex="min" max="7"/>
            </RollingRandomAccessFile>

            <RollingRandomAccessFile name="SecurityLog" fileName="${config:server.directories.logs}/security.log"
                                     filePattern="$${config:server.directories.logs}/security.log.%02i">
                <JsonTemplateLayout eventTemplateUri="classpath:org/neo4j/logging/StructuredLayoutWithMessage.json"/>
                <Policies>
                    <SizeBasedTriggeringPolicy size="20 MB"/>
                </Policies>
                <DefaultRolloverStrategy fileIndex="min" max="7"/>
            </RollingRandomAccessFile>
        </Appenders>

        <Loggers>
            <!-- Log levels. One of DEBUG, INFO, WARN, ERROR or OFF -->

            <!-- The debug log is used as the root logger to catch everything -->
            <Root level="INFO">
                <AppenderRef ref="DebugLog"/> <!-- Keep this -->
                <AppenderRef ref="console"/>
            </Root>
            <!-- The query log, must be named "QueryLogger" -->
            <Logger name="QueryLogger" level="INFO" additivity="false">
                <AppenderRef ref="QueryLog"/>
                <AppenderRef ref="console"/>
            </Logger>
            <!-- The http request log, must be named "HttpLogger" -->
            <Logger name="HttpLogger" level="INFO" additivity="false">
                <AppenderRef ref="HttpLog"/>
                <AppenderRef ref="console"/>
            </Logger>
            <!-- The security log, must be named "SecurityLogger" -->
            <Logger name="SecurityLogger" level="INFO" additivity="false">
                <AppenderRef ref="SecurityLog"/>
                <AppenderRef ref="console"/>
            </Logger>
        </Loggers>
    </Configuration>
  

Further reading:

https://neo4j.com/docs/operations-manual/current/monitoring/logging/