Rules of AEM

ACL's and how they are evaluated ? AEM Developers, Infrastructure Engineers / Dev-ops teams working in any domain regularly come across a challenge for understanding the ACL & its evaluation mechanism.  Adobe Experience Manager is designed to cater for content authoring of multiple sites by multiple content authors. Naturally, this process needs to be controlled by strict Access Control Lists (ACLs) to manage. AEM WCM uses Access Control Lists (ACLs) to organise the permissions being applied to the various pages. This article addresses in a simple way on how to understand the ACL's , its different ways,  This article covers the following - How can we read and understand the ACL.  Evaluation of user permissions.  Concurrent Permission on ACL Access Control Lists are made up of the individual permissions and are used to determine the order in which these permissions are actually applied. The list is formed according to the hierarchy of the pages under consideration...

How Does S3 works with AEM  ? Accommodating a huge amount of assets in any content management platform is challenging. Adobe Experience Manager offers an integration with the Amazon S3 storage solution, allowing binary data for images, documents and videos to be stored in an S3 bucket. Amazon S3 is highly performant and offers nearly infinite storage capacity.   When talking about terabyte storage, performance is everything. The choices made during the planning and architecting phase can literally make or break the performance of a CMS system and the websites running on it.  Adobe Experience Manager offers a number of storage methods, each offering a different way of storing data. Each of these options has its strengths and weaknesses. In AEM storage the mechanisms are called Micro Kernels, or MK for short.  In this article we will look at the AEM with S3 data store. For the detailed steps for S3 configuration you can refer -  https://www.aemrules.com/...

 Maven build is failing due to CHECKSUM issue.  AEM Developers, Infrastructure Engineers regularly come across a challenge on building the AEM code & dispatcher module use to get failed while mvn build. The article addresses in a simple way on how to understand the mechanisms of dispatcher module build, and gives a detailed explanation of how it can be resolved.  This is useful for  building the code for a deployment via Pipeline either it is Adobe Cloud manager or Jenkins, you can see this error while your local build itself.  This error is caused, as the dispatcher owner does not not want you to change/modify few of its default files which are marked as immutable in dispatcher server.  You can find full list of immutable files on of dispatcher provided by Adobe.  https://helpx.adobe.com/experience-manager/kb/ams-dispatcher-manual/immutable-files.html Issue :- In AEM while doing the deployment it is being seen , user get the exception , Maven ma...

 SSL handshake error while replication  While configuring the SSL between author and publish servers, for a secured data flow you want to make the replication calls also over HTTPS.  Assumption -      Author and publish servers will have working SSL and sling security check should be pass.  Error -   Replication test  failed PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target   OR    Error while sending request: javax.net.ssl.SSLPeerUnverifiedException: peer not authenticated Cause -  This issue comes as replication agents try to find the certificates with exact name. and it ignores the wild card certificates.  Solution  -  Login to AEM , open replication agent which has the error. Edit the replication agent Go to transport  Make ssl to R elaxed . 

ERROR :-   OakAccess0000: Access denied We often observe while doing the AEM development or in live running environment we get the error code  OakAccess0000 , while running a workflow or any asset upload.  This impact the business as content author are unable to upload any content.  Error stack trace :- Javax.jcr.AccessDeniedException: OakAccess0000: Access denied  at org.apache.jackrabbit.oak.api.CommitFailedException.asRepositoryException(CommitFailedException.java:232) [org.apache.jackrabbit.oak-api:1.10.6]  at org.apache.jackrabbit.oak.api.CommitFailedException.asRepositoryException(CommitFailedException.java:213) [org.apache.jackrabbit.oak-api:1.10.6]  at org.apache.jackrabbit.oak.jcr.delegate.SessionDelegate.newRepositoryException(SessionDelegate.java:669) [org.apache.jackrabbit.oak-jcr:1.10.6]  at org.apache.jackrabbit.oak.jcr.delegate.SessionDelegate.save(SessionDelegate.java:495) [org.apache.jackrabbit.oak-jcr:1.10.6]  at org.ap...

Added Security in AEM via Headers:-  In design a robust architecture AEM Architects, Developers, Infrastructure Engineers regularly come across a challenge for adding the additional security in AEM.  In this article, we will understand the key security headers which can be used in webserver and give an additional layer of security for your Publish server and content.  I have used Apache webserver for all the examples.  This article covers -  1 - X-XSS protection  2 - HTTP Strick Transport Security 3 - X-Frame Option  4 - Content Security  1- X-XSS Protection:-  X-XSS-Protection header can prevent some level of XSS (cross-site-scripting ) attacks.  Configure the x-xss-protection header to 1 in your apache httpd.conf file or Vhost file if you have for all domains as applicable.   <IfModule mod_headers.c>   <FilesMatch "\.(htm|html)$">               ...

AEM Developers, Infrastructure Engineers / Dev-ops teams working in the financial domain regularly come across a challenge for event auditing in AEM. This helps in identifying most of the activities happening in AEM. Audit logs are a very effective way to debug the content issue & to know what all is happening in your environment and by whom. This article addresses in a simple way on how to enable the audit logs, its different ways, and how to understand the audit logs.  This article covers the following - How can we enable Audit logs in AEM. How can we read and understand the Audit logs/ tools to use it. Audit log on file system in crx-quickstart/logs folder.   Audit logs for User creation / Modification. How can you archive/purge the audit logs. How can we enable Audit logs in AEM?            By Default, the Audit logs are pre-configured in AEM, for a few basic operations of DAM and for all other operations of Pages ...

AEM DISPATCHER STATFILE UNDERSTANDING & CACHE INVALIDATION:- AEM Developers, Infrastructure Engineers regularly come across a challenge on decoding the statfile and using it efficiently especially statfile becomes highly relevant in a multi-tenanted environment with different project teams controlling different sites. The article addresses in a simple way on how to understand the mechanisms of stat file and gives a detailed explanation of how it can be used in a multi-tenant environment model.  The image for your reference as a quick overview of the data flow, before we take a deep dive.  This article covers - 1 - When dispatcher serves the old version of the content. How to avoid it. 2- Cache invalidation mechanism. Assumption - If you are reading this article, I believe you would have a basic understanding of Dispatcher and it's configuration. Firstly let’s set the initial configuration for the cache invalidation section ...