>> But we would not like to disable the offlining of the undo segment, we >> would >> like just not to generate the traces or instead send the onlined undo >> notification to the alert log. Any ideas on it? And again, this doesn't meet you requerements completely,it's just another possible solution :):):), provided by OSS, for a similar case. Bug NO. 3553507 SERVER PROCESSES WRITE MESSAGES OF UNDO SEGMENTS TO TRACE FILES PROBLEM: When startup or shutdown database , server process writes next 3 messages to trace file every time. . Undo Segment 1 Onlined ANALYSIS: When set undo_management=manual, these messages don't write to trace files. . WORKAROUND: set undo_management=manual Regards Dimitre