3.2. Configuration Version

When a node joins the cluster, the cluster will perform a check to see who has the best configuration based on the fields below. It then asks the node with the highest (admin_epoch, epoch, num_updates) tuple to replace the configuration on all the nodes - which makes setting them, and setting them correctly, very important.

Table 3.1. Configuration Version Properties

Field	Description
`admin_epoch`	Never modified by the cluster. Use this to make the configurations on any inactive nodes obsolete. Never set this value to zero, in such cases the cluster cannot tell the difference between your configuration and the "empty" one used when nothing is found on disk.
`epoch`	Incremented every time the configuration is updated (usually by the admin)
`num_updates`	Incremented every time the configuration or status is updated (usually by the cluster)