Logging for AEM as a Cloud Service logging-for-aem-as-a-cloud-service

AEM as a Cloud Service is a platform for customers to include custom code to create unique experiences for their customer base. With this in mind, the logging service is a critical function to debug and understand code execution on local development, and cloud environments, particularly the AEM as a Cloud Service’s Dev environments.

AEM as a Cloud Service logging settings and log levels are managed in configuration files that are stored as part of the AEM project in Git, and deployed as part of the AEM project via Cloud Manager. Logging in AEM as a Cloud Service can be broken into three logical sets:

AEM Logging aem-logging

Logging at the AEM application level, is handled by three logs:

AEM Java Logging aem-java-logging

AEM as a Cloud Service’s provides access to Java log statements. Developers of applications for AEM should follow general Java logging best practices, logging pertinent statements about the execution of custom code, at the following log levels:

While Java logging supports several other levels of logging granularity, AEM as a Cloud Service recommends using the three levels described above.

AEM Log levels are set per environment type via OSGi configuration, which in turn are committed to Git, and deployed via Cloud Manager to AEM as a Cloud Service. Because of this, it is best to keep log statements consistent and well known for environment types to ensure the logs available via AEM as Cloud Service are available at the optimal log level without requiring redeployment of application with the updated log level configuration.

Example Log Output

22.06.2020 18:33:30.120 [cm-p12345-e6789-aem-author-86657cbb55-xrnzq] *ERROR* [qtp501076283-1809] io.prometheus.client.dropwizard.DropwizardExports Failed to get value from Gauge
22.06.2020 18:33:30.229 [cm-p12345-e6789-aem-author-86657cbb55-xrnzq] *INFO* [qtp501076283-1805] org.apache.sling.auth.core.impl.SlingAuthenticator getAnonymousResolver: Anonymous access not allowed by configuration - requesting credentials
22.06.2020 18:33:30.370 [cm-p12345-e6789-aem-author-86657cbb55-xrnzq] *INFO* [73.91.59.34 [1592850810364] GET /libs/granite/core/content/login.html HTTP/1.1] org.apache.sling.i18n.impl.JcrResourceBundle Finished loading 0 entries for 'en_US' (basename: <none>) in 4ms
22.06.2020 18:33:30.372 [cm-p12345-e6789-aem-author-86657cbb55-xrnzq] *INFO* [FelixLogListener] org.apache.sling.i18n Service [5126, [java.util.ResourceBundle]] ServiceEvent REGISTERED
22.06.2020 18:33:30.372 [cm-p12345-e6789-aem-author-86657cbb55-xrnzq] *WARN* [73.91.59.34 [1592850810364] GET /libs/granite/core/content/login.html HTTP/1.1] libs.granite.core.components.login.login$jsp j_reason param value 'unknown' cannot be mapped to a valid reason message: ignoring

Log Format

Configuration Loggers configuration-loggers

AEM Java logs are defined as OSGi configuration, and thus target specific AEM as a Cloud Service environments using run mode folders.

Configure java logging for custom Java packages via OSGi configurations for the Sling LogManager factory. There are three supported configuration properties:

Changing other LogManager OSGi configuration properties may result in availability issues in AEM as a Cloud Service.

The following are examples of the recommended logging configurations (using the placeholder Java package of com.example) for the three AEM as a Cloud Service environment types.

Development development

/apps/my-app/config/org.apache.sling.commons.log.LogManager.factory.config-example.cfg.json

{
    "org.apache.sling.commons.log.names": ["com.example"],
    "org.apache.sling.commons.log.level": "debug"
    "org.apache.sling.commons.log.file": "logs/error.log"
}

Stage stage

/apps/my-app/config.stage/org.apache.sling.commons.log.LogManager.factory.config-example.cfg.json

{
    "org.apache.sling.commons.log.names": ["com.example"],
    "org.apache.sling.commons.log.level": "warn"
    "org.apache.sling.commons.log.file": "logs/error.log"
}

Production productiomn

/apps/my-app/config.prod/org.apache.sling.commons.log.LogManager.factory.config-example.cfg.json

{
    "org.apache.sling.commons.log.names": ["com.example"],
    "org.apache.sling.commons.log.level": "error"
    "org.apache.sling.commons.log.file": "logs/error.log"
}

AEM HTTP Request Logging aem-http-request-logging

AEM as a Cloud Service’s HTTP request logging provides insight into the HTTP requests made to AEM and their HTTP responses in time order. This log is helpful to understand the HTTP Requests made to AEM and the order they are processed and responded to.

The key to understanding this log is mapping the HTTP request and response pairs by their IDs, denoted by the numeric value in the brackets. Often requests and their corresponding responses have other HTTP requests and responses interjected between them in the log.

Example Log

29/Apr/2020:19:14:21 +0000 [137] > POST /conf/global/settings/dam/adminui-extension/metadataprofile/ HTTP/1.1 [cm-p1234-e5678-aem-author-59555cb5b8-q7l9s]
...
29/Apr/2020:19:14:22 +0000 [139] > GET /mnt/overlay/dam/gui/content/processingprofilepage/metadataprofiles/editor.html/conf/global/settings/dam/adminui-extension/metadataprofile/main HTTP/1.1 [cm-p1234-e5678-aem-author-59555cb5b8-q7l9s]
...
29/Apr/2020:19:14:21 +0000 [137] <- 201 text/html 111ms [cm-p1234-e5678-aem-author-59555cb5b8-q7l9s]
...
29/Apr/2020:19:14:22 +0000 [139] <- 200 text/html;charset=utf-8 637ms [cm-p1234-e5678-aem-author-59555cb5b8-q7l9s]

Log Format

Configuring the Log configuring-the-log

The AEM HTTP Request log is not configurable in AEM as a Cloud Service.

AEM HTTP Access Logging aem-http-access-logging

AEM as Cloud Service HTTP access logging shows HTTP requests in time order. Each log entry represents the HTTP Request that accesses AEM.

This log is helpful to quickly understand what HTTP requests are being made to AEM, if they succeed by looking at the accompanying HTTP response status code, and how long the HTTP request took to complete. This log can also be helpful to debug a specific user’s activity by filtering log entries by Users.

Example Log Output

cm-p1234-e26813-aem-author-59555cb5b8-8kgr2 - example@adobe.com 30/Apr/2020:17:37:14 +0000  "GET /libs/granite/ui/references/clientlibs/references.lc-5188e85840c529149e6cd29d94e74ad5-lc.min.css HTTP/1.1" 200 1141 "https://author-p10711-e26813.adobeaemcloud.com/mnt/overlay/dam/gui/content/assets/metadataeditor.external.html?item=/content/dam/en/images/example.jpeg&_charset_=utf8" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.122 Safari/537.36"
cm-p1234-e26813-aem-author-59555cb5b8-8kgr2 - example@adobe.com 30/Apr/2020:17:37:14 +0000  "GET /libs/dam/gui/coral/components/admin/customthumb/clientlibs.lc-60e4443805c37afa0c74b674b141f1df-lc.min.css HTTP/1.1" 200 809 "https://author-p10711-e26813.adobeaemcloud.com/mnt/overlay/dam/gui/content/assets/metadataeditor.external.html?item=/content/dam/en/images/example.jpeg&_charset_=utf8" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.122 Safari/537.36"
cm-p1234-e26813-aem-author-59555cb5b8-8kgr2 - example@adobe.com 30/Apr/2020:17:37:14 +0000  "GET /libs/dam/gui/coral/components/admin/metadataeditor/clientlibs/metadataeditor.lc-4a2226d8232f8b7ab27d24820b9ddd64-lc.min.js HTTP/1.1" 200 7965 "https://author-p10711-e26813.adobeaemcloud.com/mnt/overlay/dam/gui/content/assets/metadataeditor.external.html?item=/content/dam/en/images/example.jpeg&_charset_=utf8" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.122 Safari/537.36"

Configuring the HTTP Access Log configuring-the-http-access-log

The HTTP Access log is not configurable in AEM as a Cloud Service.

Apache Web Server and Dispatcher Logging apache-web-server-and-dispatcher-logging

AEM as a Cloud Service provides three logs for the Apache Web Servers and dispatcher layer on the Publish:

These logs are only available for the Publish tier.

This set of logs provides insights into HTTP requests to the AEM as a Cloud Service Publish tier prior to those requests reaching the AEM application. This is important to understand as, ideally, most HTTP requests to the Publish tier servers are served by content that is cached by the Apache HTTPD Web Server and AEM Dispatcher, and never reach the AEM application itself. Thus there are no log statements for these requests in AEM’s Java, Request or Access logs.

Apache HTTPD Web Server Access Log apache-httpd-web-server-access-log

The Apache HTTP Web Server access log provides statements for each HTTP request that reaches the Publish tier’s Web server/Dispatcher. Requests that are served from an upstream CDN are not reflected in these logs.

See information about the error log format in the official apache documentation.

Example Log Output

cm-p1234-e5678-aem-publish-b86c6b466-qpfvp - - 17/Jul/2020:09:14:41 +0000  "GET /etc.clientlibs/wknd/clientlibs/clientlib-site/resources/images/favicons/favicon-32.png HTTP/1.1" 200 715 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Firefox/78.0"
cm-p1234-e5678-aem-publish-b86c6b466-qpfvp - - 17/Jul/2020:09:14:41 +0000  "GET /etc.clientlibs/wknd/clientlibs/clientlib-site/resources/images/favicons/favicon-512.png HTTP/1.1" 200 9631 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Firefox/78.0"
cm-p1234-e5678-aem-publish-b86c6b466-qpfvp - - 17/Jul/2020:09:14:42 +0000  "GET /etc.clientlibs/wknd/clientlibs/clientlib-site/resources/images/country-flags/US.svg HTTP/1.1" 200 810 "https://publish-p6902-e30226.adobeaemcloud.com/content/wknd/us/en.html" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Firefox/78.0"

Log Format

Configuring the Apache HTTPD Web Server Access Log configuring-the-apache-httpd-webs-server-access-log

This log is not configurable in AEM as a Cloud Service.

Apache HTTPD Web Server Error Log apache-httpd-web-server-error-log

The Apache HTTP Web Server error log provides statements for each error in the Publish tier’s Web server/Dispatcher.

See information about the error log format in the official apache documentation.

Example Log Output

Fri Jul 17 02:19:48.093820 2020 [mpm_worker:notice] [pid 1:tid 140272153361288] [cm-p1234-e30226-aem-publish-b86c6b466-b9427] AH00292: Apache/2.4.43 (Unix) Communique/4.3.4-20200424 mod_qos/11.63 configured -- resuming normal operations
Fri Jul 17 02:19:48.093874 2020 [core:notice] [pid 1:tid 140272153361288] [cm-p1234-e30226-aem-publish-b86c6b466-b9427] AH00094: Command line: 'httpd -d /etc/httpd -f /etc/httpd/conf/httpd.conf -D FOREGROUND -D ENVIRONMENT_PROD'
Fri Jul 17 02:29:34.517189 2020 [mpm_worker:notice] [pid 1:tid 140293638175624] [cm-p1234-e30226-aem-publish-b496f64bf-5vckp] AH00295: caught SIGTERM, shutting down

Log Format

Configuring the Apache HTTPD Web Server Error Log configuring-the-apache-httpd-web-server-error-log

The mod_rewrite log levels are defined by the variable REWRITE_LOG_LEVEL in the file conf.d/variables/global.var.

It can be set to error, warn, info, debug and trace1 - trace8, with a default value of warn. To debug your RewriteRules, it is recommended to raise the log level to trace2. It’s recommended to debug rewrite rules using the Dispatcher SDK. The maximal log level for AEM as a Cloud Service is debug. Thus it is currently not effectively possible to debug rewrite rules in the cloud.

See the mod_rewrite module documentation for more information.

To set the log level per environment, use the appropriate conditional branch in the global.var file, as described below:

Define REWRITE_LOG_LEVEL debug

<IfDefine ENVIRONMENT_STAGE>
  ...
  Define REWRITE_LOG_LEVEL warn
  ...
</IfDefine>
<IfDefine ENVIRONMENT_PROD>
  ...
  Define REWRITE_LOG_LEVEL error
  ...
</IfDefine>

Dispatcher Log dispatcher-log

Example

[17/Jul/2020:23:48:06 +0000] [I] [cm-p12904-e25628-aem-publish-6c5f7c9dbd-mzcvr] "GET /content/wknd/us/en/adventures.html" - 475ms [publishfarm/0] [action miss] "publish-p12904-e25628.adobeaemcloud.com"
[17/Jul/2020:23:48:07 +0000] [I] [cm-p12904-e25628-aem-publish-6c5f7c9dbd-mzcvr] "GET /content/wknd/us/en/adventures/climbing-new-zealand/_jcr_content/root/responsivegrid/carousel/item_1571266094599.coreimg.jpeg/1473680817282/sport-climbing.jpeg" 302 10ms [publishfarm/0] [action none] "publish-p12904-e25628.adobeaemcloud.com"
[17/Jul/2020:23:48:07 +0000] [I] [cm-p12904-e25628-aem-publish-6c5f7c9dbd-mzcvr] "GET /content/wknd/us/en/adventures/ski-touring-mont-blanc/_jcr_content/root/responsivegrid/carousel/item_1571168419252.coreimg.jpeg/1572047288089/adobestock-238230356.jpeg" 302 11ms [publishfarm/0] [action none] "publish-p12904-e25628.adobeaemcloud.com"

Log Format

Configuring the Dispatcher Error Log configuring-the-dispatcher-error-log

The dispatcher log levels is defined by the variable DISP_LOG_LEVEL in the file conf.d/variables/global.var.

It can be set to error, warn, info, debug and trace1, with a default value of warn.

While Dispatcher logging supports several other levels of logging granularity, the AEM as a Cloud Service recommends using the levels described below.

To set the log level per environment, use the appropriate conditional branch in the global.var file, as described below:

Define DISP_LOG_LEVEL debug

<IfDefine ENVIRONMENT_STAGE>
  ...
  Define DISP_LOG_LEVEL warn
  ...
</IfDefine>
<IfDefine ENVIRONMENT_PROD>
  ...
  Define DISP_LOG_LEVEL error
  ...
</IfDefine>

CDN Log cdn-log

AEM as a Cloud Service provides access to CDN logs, which are useful for use cases including cache hit ratio optimization. The CDN log format cannot be customized and there is no concept of setting it to different modes such as info, warn, or error.

Example

{
"timestamp": "2023-05-26T09:20:01+0000",
"ttfb": 19,
"cli_ip": "147.160.230.112",
"cli_country": "CH",
"rid": "974e67f6",
"req_ua": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/14.0.3 Safari/605.1.15",
"host": "example.com",
"url": "/content/hello.png",
"method": "GET",
"res_ctype": "image/png",
"cache": "PASS",
"status": 200,
"res_age": 0,
"pop": "PAR",
"rules": "match=Enable-SQL-Injection-and-XSS-waf-rules-globally,waf=SQLI,action=blocked"
}

Log Format

The CDN logs are distinct from the other logs in that it adheres to a json format.

How to Access Logs how-to-access-logs

Cloud Environments cloud-environments

AEM as a Cloud Service logs for cloud services can be accessed either by downloading through the Cloud Manager interface or by tailing logs at the command line using the using the Adobe I/O command line interface. For more information, see the Cloud Manager logging documentation.

Logs for Additional Publish Regions logs-for-additional-publish-regions

If additional publish regions are enabled for a particular environment, logs for each region will be available to download from Cloud Manager, as mentioned above.

The AEM logs and the dispatcher logs for the additional publish regions will specify the region in the first 3 letters after the environment id, as exemplified by nld2 in the sample below, which refers to an additional AEM publish instance located in the Netherlands:

cm-p7613-e12700-nld2-aem-publish-bcbb77549-5qmmt 127.0.0.1 - 07/Nov/2023:23:57:11 +0000 "HEAD /libs/granite/security/currentuser.json HTTP/1.1" 200 - "-" "Java/11.0.19"

Local SDK local-sdk

AEM as a Cloud Service SDK provides logs files to support local development.

AEM logs are located in the folder crx-quickstart/logs, where the following logs can be viewed:

Apache layer logs, including dispatcher, are in the Docker container which holds the Dispatcher. See the Dispatcher documentation for information on how to start the Dispatcher.

To retrieve the logs:

Logs are also directly printed to the terminal output. Most of the time, these logs should be DEBUG, which can be accomplished by passing in the Debug level as a parameter when running Docker. For example:

DISP_LOG_LEVEL=Debug ./bin/docker_run.sh out docker.for.mac.localhost:4503 8080

Debugging Production and Stage debugging-production-and-stage

In exceptional circumstances, log levels need to be changed to log at a finer granularity in Stage or Production environments.

While this is possible, it requires changes to the log levels in the configuration files in Git from Warn and Error to Debug, and performing a deployment to AEM as a Cloud Service to register these configuration changes with the environments.

Depending on the traffic and the amount of log statement written by Debug, this may result in an adverse performance impact on the environment, therefore, it’s recommended that changes to Stage and Production debug levels are:

Log Forwarding log-forwarding

While logs can be downloaded from Cloud Manager, some organizations find it benficial to forward those logs to a preferred logging destination. AEM supports streaming logs to the following destinations:

Refer to the Log Forwarding article for details on how to configure this feature.