请帮助分析tsm备份oracle出现报错日志

大家好。这几天发现tsm备份oracle出现问题。

运行q event * *

Scheduled Start          Actual Start             Schedule Name     Node Name         Status   

--------------------     --------------------     -------------     -------------     ---------                                   

12/21/15   07:00:00      12/21/15   07:00:03      DB02_SC-     DB02         Failed 12

检查dsmerror.log

12/12/15   07:00:07 ANS1909E The scheduled command failed.

12/12/15   07:00:07 ANS1512E Scheduled event 'YYDB02_SCH1' failed.  Return code = 12.

12/17/15   07:00:05 ANS1351E Session rejected: All server sessions are currently in use

12/17/15   07:00:06 ANS1909E The scheduled command failed.

12/17/15   07:00:06 ANS1512E Scheduled event 'YYDB02_SCH1' failed.  Return code = 12.

12/18/15   07:00:05 ANS1351E Session rejected: All server sessions are currently in use

12/18/15   07:00:06 ANS1909E The scheduled command failed.

12/18/15   07:00:06 ANS1512E Scheduled event 'YYDB02_SCH1' failed.  Return code = 12.

12/19/15   07:00:05 ANS1351E Session rejected: All server sessions are currently in use

12/19/15   07:00:06 ANS1909E The scheduled command failed.

12/19/15   07:00:06 ANS1512E Scheduled event 'YYDB02_SCH1' failed.  Return code = 12.

12/20/15   07:00:05 ANS1351E Session rejected: All server sessions are currently in use

12/20/15   07:00:06 ANS1909E The scheduled command failed.

12/20/15   07:00:06 ANS1512E Scheduled event YYDB02_SCH1' failed.  Return code = 12.

12/21/15   07:00:05 ANS1351E Session rejected: All server sessions are currently in use

请问这个是什么原因导致。如何解决。

谢谢