Solved
AEM 6 Clustering
I have tried clustering in AEM 6 using GUI approach as well as the GUI based approach, however am unable to do so. Nee help in clustering 2 instances.
Attaching are the error shown by the two methods.
Those methods only work (as the second screenshot shows) when using CRX2. You are presumably using Oak (which is the default with AEM 6). In Oak, clustering works only when using MongoMK as descrbied here: http://docs.adobe.com/docs/en/aem/6-0/deploy/recommended-deploys.html