When Vontu processes are run as 'local' user, processes can fail.
When Vontu is installed, a user account is created called "protect". If this account is deleted or goes missing for whatever reason, processes will run as 'local' user, which can cause processes to fail. For example, when Vontu processes are run as 'local' user, there might not be permissions to write to the Vontu directory and this can cause the Vontu processes to fail.
If you are seeing any authentication errors in the logs, check that the processes are run by the 'protect' user, and not 'local' user.Always run Vontu processes as either 'protect' or 'protect_update' to ensure that all Vontu processes run correctly.