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Also, the property auth_token_key should be set up in the poller configuration.
More information about authorisation/authentication in opHA.
Other causes
Another potential cause of a 401 error is the linux system clock on the Poller being too far out of sync with the Primary. In this case, you may see an error similar to below, where the auth.log is showing an info message about the token for the user being expired. Ensuring the clocks are in sync will resolve this issue.
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