There's section in the guide called "migrating from talend log server 6.5 to 7.1" which is concerning me. Do we need to upgrade from 6.3 to 6.5 first, and if so, is there a guide for that?
With your subscription solution, could you please create a support case on talend support portal? In this way, our colleagues from support team will give you a remote assistance for your upgrading and migration issue through support cycle with priority.
