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If this is a login error, please review the credentials used are correct in the poller. You can check the file log/auth.log from the poller.
opHA cluster_id already exist!
Check the master and all other pollers nmis configuration for the cluster_id property. It can be found in 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 the property in the configuration file and nmis will generate a new one.
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).
401 Error from the poller
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