TL;DR: will data nodes be offline during reindexing after a major upgrade (1.x -> 2.x)?
Our DEV cluster has 4 nodes - 2 pure data nodes, 1 master and 1 client-only node.
I understand that after upgrading the indexes will be rebuilt (new version of Lucene, etc.), and also that I had to setup unicast since multicast is no longer used for discovery.
The configuration changes I made are as follow:
network.host: _eth0_ discovery.zen.ping.multicast.enabled: false discovery.zen.ping.unicast.hosts: ["10.x.x.x"]
Where the value in the unicast.hosts property is the IP address of the single master node. The above are set the same on all four boxes.
So after upgrading all the nodes, I see the two data nodes are maxing out CPU frequently, seem active in rebuilding the index (which I understood to be normal). The issue is that when I hit the client node the only available nodes on the cluster appear to be my master & client nodes; the data nodes aren't showing as part of the cluster (looking at
Is this normal? Will the data nodes be offline until reindexing is complete?