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Check the Primary and all other pollers nmis configuration for the cluster_id property. It can be found in /usr/local/nmis9/conf/Config.nmis. This one should be unique per server, so in case one of the pollers has a repeated one you can remove delete the property in the configuration file, restart the nmis9d daemon, and nmis will generate a new one.
NOTE: The Opmantek VM ships with the cluster_id preset. In instances where multiple Opmantek VMs are deployed, and connected using opHA, the cluster_id will need to be changed/update on each server. This should be done PRIOR to adding any nodes/devices to the cluster.
Please, notice that in case the server has nodes already, the nodes should be exported and imported again with localised_ids once the cluster_id was changed, as the nodes information won't have the same cluster_id attribute and they will be treated as remote nodes (They cannot be edited, or polled, as an example).
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