I am trying to setup my environment so that I can switch from using tribe nodes to use cross cluster search and running in to a few problems

After some useful feedback in this forum I have configured my system with kibana pointing to a coordinating node in **cluster_1** with cross cluster search configured so I can also search indices in **cluster_2** and **cluster_3**.

I  can configure index patterns in Kibana to search for logs as follows:-

logstash-*                       returns all local logs in cluster_1 successfully
cluster_2:logstash-*      returns all logs in remote cluster_2 successfully
cluster_3:logstash-*      returns all logs in remote cluster_3 successfully
\*:logstash-*                    returns all logs in remote cluster_2 and cluster_3 successfully

Question1. Is there a way to set up an index pattern to query all logs in all 3 clusters i.e. local and remote clusters ?

Question 2. Is there a way to search specific remote clusters ?   I have tried the documented syntax of **cluster_2,cluster_3:logstash-*** and in Kibana 5.6.2 it does not work