Hi Ravishankar,
If issue reoccurred then need to upgrade to the latest release of SEP i.e. SEP 12.1 RU4.
According to SEP 12.1 RU4 fix notes, it's a known issue.
Log file size grows to be very large
Fix ID: 3162820
Symptom: Log messages continue to write to scm-ui.log, even after the user logs out of the console. As a result, the log file grows very large.
Solution: Limited the size of scm-ui.log and scm-ui.err, which are configurable in the conf.properties file. Modified the method of logging System.out, System.err and other console logging
Reference: New fixes and features in Symantec Endpoint Protection 12.1.4
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