Issue adding a new author instance to an existing AEM 6.2 Author cluster

[sajidm85330797]

Hello,

I need some assistance on an issue that I am facing with my author cluster.  I have my author cluster set up to use Mongo.  The initial process is to start one author and wait until the instance is fully up and running before adding another author instance to the cluster.  At this time, I have not found a way to start multiple authors simultaneously.  Once the first author is started, I am able to scale my cluster up and down without any issues, assuming no new application packages have been installed on the first author instance.  My scenario is to start with a 2 Author node cluster with custom application and content installed.  After the application and content installation, I scaled the author nodes to total of 3 author instances.  In scaling up the additional author which does not contain the custom application or content, the start up process of the new author causes the other authors to start restarting their OSGi bundles which cause the author cluster to go offline due to the OSGi bundles restarting.  I am trying to figure out how to prevent the new author from causing an OSGi restart on the existing author instances.  To replicate this issue, execute below step:

1. Start Mongo db
2. Start AEM author configured to Mongo with the `samplecontent` runmode.
3. After the first AEM author instance is up, start second AEM author configured to Mongo with the `nosamplecontent` runmode.
4. If you are watching the logs, you will see the first author instance will start to unregister and register OSGi bundles.

Let me know if anyone has figured out what the issue I am facing.  The logs for both author instances can be found here, https://drive.google.com/open?id=0B_axgPTf1l7yUXpXay1uZDh0U2c.

Sajid

[MC_Stuff · Accepted solution]

Hi Sajid, 

     After the cluster has been setup the leader has to sync to all nodes the changes.  In order for leader to know all the nodes need a restart and as you know sync happens at lower level. Installation is one time setup & to scale later need an little downtime.  IIRC Norberto Leite from mongodb covered this question in one of the training where there was some steps to reduce the down time.   Adobe has special program to get access to all mongodb trainings materials & you can reach official support team to get more details on the program.  

Thanks,