This problem can be caused by many different reasons. Follow all steps of this check list to find out the root cause of the problem:
1. Check that your Support Package level is higher than:
R/3 620 - 60
R/3 640 - 18
R/3 700 - 09
Otherwise apply SAP 1019847.
2. Check if standard job SAP_COLLECTOR_FOR_PERFMONITOR is scheduled hourly and run successfully. Go to transaction SM37 and check the execution of this job during the last days. It is also important that it is scheduled only once per hour and close to o'clock (it has been recently observed that jobs planned at half past or at anytime not close to o'clock may not collect data correctly). For more general information about standard jobs refer to SAP 16083.
3. Check if report RSORACOL is contained in table TCOLL. Go to transaction SE16 and show the contents of table TCOLL. You should find the entry:
RNAME RSORACOL
RENUM 1
SYTYP S (or C if 620)
ALTSY
DAYOW XXXXXXX
TIMOD XXXXXXXXXXXXXXXXXXXXXXXX
For more information refer to SAP 12103 for 620, 970449 for 640, 966309 for 700 and 966631 for 710.
4. Check if your monitored database is contained in table ORA_MON_DBCON and it is active (STATUS=A). Go to transaction SE16 and show the contents of table ORA_MON_DBCON. For the local database your should find an entry like:
CON NAME DEFAULT
STATUS A
MAX RUNTIME 1.800
MAX UPLOAD 1.000.000
LOG LIFE 100
DESCRIPTION Local Oracle database
Note that the name "DEFAULT" is mandatory for the local database, as the collector code is hard coded with this string.
In case you also want to monitor a remote database you should find an entry like:
CON NAME DBX_UNIC1
STATUS A
MAX RUNTIME 1.800
MAX UPLOAD 1.000.000
LOG LIFE 100
DESCRIPTION Remote Oracle database
Note that this database must have been previously maintained in transaction DBCO. For more information about remote DB native connection refer to SAP 323151 and 339092. (As well remember that, in case you have not maintained this database in transaction DBCO, it should not show up within the F4 help of report RSORACUP)
In case the status column shows inactive (I), it is most probably caused by connection errors during the collection job. Therefore check your DB connections.
5. Check if all collector modules are contained in table DB02_COLL_PLAN and are active (STATUS=A). Go to DB02->Additional functions->Collector logs->Click on tab "Modules". You should find around 60 to 65 modules (the exact number depend on your R/3 release/patch). All modules must be active (STATUS=A). If not, then refer to the collection log to know the causes about its deactivation. You can find the collection log in table DB02_COLL_LOG. Go to transaction SE16 and display only entries of DB02_COLL_LOG for the affected SMON_ID. Normally you only need to check the return code of the last collection date ever. The meaning of each return code is the following:
00 Successful execution
01 Successful execution: no data collected
02 Successful execution: dataset was already up-to-date
10 Database connection not possible
20 Monitor deactivated: Oracle release < 9
30 Submonitor deactivated: source submonitor was inactive
31 Submonitor deactivated: data upload exceeded fixed limit
32 Submonitor deactivated: runtime exceeded fixed limit
You can re-activate collector modules as follows:
1) Call report RSORACUP with parameter:
CON_NAME = <DB connection>
OPERATIO = DELETE
2) If you are asked to delete entries in MONI, say NO.
3) Call report RSORACUP again with parameters:
CON_NAME = <DB connection>
OPERATIO = CREATE
After this, the name of the DB connection is inserted in table ORA_MON_DBCON and table DB02_COLL_PLAN shows the corresponding entries, all with status active.
6. Check for possible short dumps. Go to transaction ST22 and analyze all short dumps caused by the user owner of the job SAP_COLLECTOR_FOR_PERFMONITOR. Some known errors are described in SAP:
940878 DB02N collector: ITAB_DUPLICATE_KEY
941041 DB02N not correctly set up
980367 DB02N: Improper LUW strategy for data collection
992775 ITAB_DUPLICATE_KEY in SMON_ID = 700
1019847 DB collector does not collect data
1064524 DB02 ITAB_DUPLICATE_KEY
1064524 DB02 ITAB_DUPLICATE_KEY
1066044 COMPUTE_BCD_OVERFLOW during DB02N refresh
1042725 DB02 Refresh terminates in short dump
7. DBACockpit/DB02N on rel. 700 sp. 12 is not stable. You must upgrade to sp. 13 or apply the above mentioned SAP 1066044 and 1042725.
8. It should be considered also a possible error during data displaying. I.e. the data is properly collected but it cannot be displayed due to a possible bug in the transaction DB02N itself.
9. Finally, if you cannot find out and correct the problem yourself, please open a message under component BC-CCM-MON-ORA.
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