DBMS_EPG.SET_GLOBAL

DBMS_EPG.SET_GLOBAL_ATTRIBUTE

Set log level

begin
-- See MOS Note 563704.1
   dbms_epg.set_global_attribute( 'log-level', 7 /* = LOG_DEBUG */);
end;
/

$ curl  --digest  -u 'EPG_TEST_USER:myLittleSecret' http://EPG_TEST_USER:myLittleSecret@localhost:1234/epg-test/no-such-procedure
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<HTML><HEAD>
<TITLE>400 Bad Request</TITLE>
</HEAD><BODY><H1>Bad Request</H1>
The HTTP client sent a request that this server could not understand.</BODY></HTML>

Find directory where trace files are written to, then:

$ grep -l no-such-procedure

Determine value of log level

select
   dbms_epg.get_global_attribute( 'log-level')
from
   dual;