STP is currently not cluster coherent for applications which don't require session affinity (sticky session).
I noticed at raised these concerns but none of them were fixed. Nothing was documented on the issue so my best guess is that its due to JIRA currently requiring session affinity.
Stash does not have session affinity and neither will JIRA and Confluence in the long term.
The following issues have been identified:
All Hercules scanning code only works on a single node:
It is tied to a HttpSession, storing a stateful object to the session. For scans triggered via the UI this will not work. This object is not Serializable and such cannot be retrieved from any node
Log files are node local, so the scan will only occur on the request node
Scheduled scans happen once per node and pass spring services around as data.
Support zips only contain logs about a single node