I have a 8-node Cassandra Cluster and All opscenter agents connected as shown on OpsCenter Dashboard page.
A couple days ago I found sth abnormal in Performance Metrics Graph: I can only see 2 or 3 nodes drawing the lines (e.g. Read/Write Request, Read/Write Latency) - other nodes are completely no show (maybe they're just too close to bottom? but i don't think so).
I tried to restarted agents on some nodes but looks the same.
Has anyone seen this before or what's the right steps to trouble shoot it?