These diagnostic alerts indicate when a node leaves the cluster, and when a node joins the cluster. 

アプリケーション ログに次のエラーが記録される。

INFO ; HAZELCAST ; HAZELCAST-1001 ; Node joined the cluster ; not-detected ;  ;  ; {"member":"Member [...]:... - ..."}

WARNING ; HAZELCAST ; HAZELCAST-1002 ; Node left the cluster ; not-detected ;  ;  ; {"member":"Member [...]:... - ..."}

These alerts are enabled by default in Confluence 6.11 or later. 

この問題の解決方法

There's no action required for these alerts. 

However, this information may be helpful when determining the chain of events that lead to an outage or other issue. 

このアラートを無視した場合 

These alerts are for information only. There's no action required. 

Can I change the threshold of this alert?

These alerts are not configurable.