Backend ACL: access to * by * none
config_back_db_open: line 0: warning: cannot assess the validity of the ACL scope within backend naming context
Read carefully: it's back-config that implicitly instantiates that rule, so it has nothing to do with back-monitor. Moreover, the message only pops up when you enable ACL logging, which is only useful for debugging. Only enable it when needed, and the message will disappear.
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