[ https://issues.apache.org/jira/browse/SLING-2892?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Stefan Egli resolved SLING-2892. -------------------------------- Resolution: Fixed implemented > Add simple paranoia check to detect duplicate sling.id in a cluster > ------------------------------------------------------------------- > > Key: SLING-2892 > URL: https://issues.apache.org/jira/browse/SLING-2892 > Project: Sling > Issue Type: Improvement > Components: Extensions > Affects Versions: Discovery Impl 1.0.0 > Reporter: Stefan Egli > Assignee: Stefan Egli > > Add a paranoia check to discovery.impl which detects a situation where more > than one instance in a cluster is running with the same sling.id. Such a > situation can for example occur, when the underlying repository-directory > (which includes a sling.id.file) is copied to add an additional cluster slave. > The suggested paranoia check works as follows: > Each time a heartbeat is written to the repository, the last value of the > heartbeat is checked to see if it matches the value written the last time. If > there should be another instance in the same cluster using the same sling.id, > it would have written the very same jcr-property but presumably with a > slightly different timestamp. Should the value not match to the value last > written, then a log.error is issued (with a reference to this bug and a > possible fix for the situation). > Note: this paranoia check is not 100% fool-proof, as it could be that the two > instances try to write the very same heartbeat time (same millisecond). Yet > it is considered at least a simple, stable mechanism to detect 99.9% of such > cases. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira