This check will confirm if the system clocks on each node are set within five seconds of each other. JIRA Data Center requires that the system time of each of the nodes are within five seconds for predictable behaviour. Environments lacking clock synchronisation may experience similar problems as described in the following KB:
|The health check passed successfully.||All nodes report a System Time within 5 seconds|
|System clocks of nodes are not synchronized. Difference: ||The times between nodes are out of sync and require fixing.|
|A Network Time Protocol (NTP) server has been configured.|
Ideally, when working with multi-node environments, it is best practices to set the system clock through the use of a NTP server. Consult your OS vendor and Sys Admin for more guidance on configuring an NTP server, examples below.
Configure NTP Server in Windows
|A NTP server cannot be configured.||Manually set the time of nodes to be in-sync and use other methods of keeping the times in synchronisation.|
|Different NTP servers are being used.|
Configure your environment to use the same NTP servers.
|Database issues are causing slowness during the check.|
The time stamp to compare node cluster times is databaseSystemTimeReaderFactory.getReader().getDatabaseSystemTimeMillis().In other words, the check is using the for each node for the comparison and must make a database request to confirm from within each node. If there are database issues resulting in long execution times, the check will fail.
Cluster Time Health Check