I've come across several occurrences already when one or two of our DSE Search nodes would be shown with "Down - Unresponsive" status in OpsCenter even though the node is up (i.e. I can access the Solr admin UI). Sometimes, nodetool status would also show that the node is down. But more often, it's only OpsCenter. I found out that the fix is to restart the datastax-agent service. Would could be causing this?
I'd also like to follow-up my other questions: