(转)Oracle Apps DBA Interview Questions – VI

By  Nagulu Polagani

Oracle Apps DBA Interview Questions – VI

Q: Why we need to put maintenance mode when we are applying a patch ?

A: Maintenance mode provides a clear separation between normal runtime operation of Oracle Applications and system downtime for

maintenance. Enabling the maintenance mode feature shuts down the Workflow Business Events System and sets up function security so

that no Oracle Applications functions are available to users. Used only during AutoPatch sessions, maintenance mode ensures

optimal performance and reduces downtime when applying a patch. For more information, refer to Preparing your System for Patching

in Oracle Applications Maintenance Utilities.

Q: After applying patch why we need to take snapshot and what is the use of it ??

A: Snapshot is a view of the system at specific time. In apps, Patch Wizard uses Global snapshot to determine which patches have

been applied to the system and Autopatch uses APPL_TOP snapshot to determine what patches have been applied to that APPL_TOP.

Snapshot actually records the list of files,file versions and bug fixes. Both snapshot are views, they are created once during

installation and then updated during patching. APPL_TOP snapshot information is stored in the AD_SNAPSHOTS, AD_SNAPSHOT_FILES, and

AD_SNAPSHOT_BUGFIXES tables

Q: Whether we can apply 2 patches at a time without merging them, why ??

A: We can’t apply 2 patches at a time because when patch started it will create 2 tables in db (AD_DEFERRED_JOBS AND

FND_INSTALL_PROCESSES). If you apply patches at a time both will try to create those 2 tables in db, so both will fail.

Q. After applying patch whether we can revert it back ?

A: No, as it is going to update some tables in db.

Q. Whether we need to run adpreclone everytime when we clone, why ?

A: We have to run adpreclone if there are changes in any customizations or any other tablespaces like if applied any AD patches,

Big Patches, Minipacks, ATG patches, Tech Stack, and AD Patches. If there are no changes, then i don’t think there is any need to

preclone it again.

Example: When you run adpreclone.pl, it essentially does an “alter database backup controlfile to trace” and stores the information from

that in a file within ${ORACLE_HOME}/appsutil. This represents all of the datafiles in the database at that particular time. The information

gathered at this time represents the state of the source at this time. If you does not run adpreclone.pl again when u do clone next time,

Your backup (your target) represents an earlier time (prior to the addition of that datafile), so the “create controlfile” step

that adcfgclone is doing is going to fail.

Q: Which files it will call when we run adcmctl.sh start apps/apps ?

A: It will call FNDLIBR executable, which will be located in $FND_TOP/bin.

Q: What are the main tables related to concurrent manager ?

A: FND_NODES

FND_CONCURRENT_PROCESSES (fcproc)

FND_CONCURRENT_REQUESTS (fcr)

FND_CONCURRENT_QUEUES (fcq)

FND_CONCURRENT_PROGRAMS (fcprog)

FND_EXECUTABLES

FND_CP_SERVICES

FND_CONCURRENT_QUEUE_SIZE

FND_CONCURRENT_QUEUE_CONTENT

FND_CONCURRENT_PROGRAM_SERIAL

FND_CONCURRENT_TIME_PERIODS

FND_CONCURRENT_PROCESSORS

Q: What is FNDFS ??

A: Report Review Agent(RRA) also referred by executable FNDFS is default text viewer in Oracle Applications 11i for viewing

output files and log files. As most of Applications DBA’s are not clear about Report Server and RRA.

Q: What is FNDSM ?? It has seperate name, what it is ?

A: FNDSM is executable & core component in GSM. GSM stands for Generic Service Management Framework. Oracle E-Business Suite

consist of various compoennts like Forms, Reports, Web Server, Workflow, Concurrent Manager .. Earlier each service used to start

at their own but managing these services (given that) they can be on various machines distributed across network. So Generic

Service Management is extension of Concurrent Processing which manages all your services , provide fault tolerance (If some

service is down ICM through FNDSM & other processes will try to start it even on remote server) With GSM all services are

centrally managed via this Framework.

Q: How to check whether ICM is up and running from backend ?

A: ps -ef | grep LIB

ps –ef | grep CPMGR

ps –ef | grep FNDCPMBR

$FND_TOP/sql/afcmstat.sql — Displays all the defined managers, their maximum capacity, pids, and their status.

afimchk.sql — Displays the status of ICM and PMON method in effect, the ICM’s log file, and determines if the concurrent manger

monitor is running.

afcmcreq.sql — Displays the concurrent manager and the name of its log file that processed a request.

afrqwait.sql — Displays the requests that are pending, held, and scheduled.

afrqstat.sql — Displays of summary of concurrent request execution time and status since a particular date.

afqpmrid.sql — Displays the operating system process id of the FNDLIBR process based on a concurrent request id. The process id

can then be used with the ORADEBUG utility.

afimlock.sql — Displays the process id, terminal, and process id that may be causing locks that the ICM and CRM are waiting to

get. You should run this script if there are long delays when submitting jobs, or if you suspect the ICM is in a gridlock with

another oracle process.

Q: Which component is responsible for PCP failover ?

A: When PCP is enabled, can you check that FNDSM is running on all your CCM nodes? That process is mainly reponsible to getting

the failovers to happen and also start up CCMs

Q: Where custom top information will be there ?

A: $APPL_TOP/APPLSYS.env file.

Q: What will happen when we run adpreclone ?

A: It will collect all info of the environment and store in seperate template files.

Q: Which two parameters are required when we do clone using RMAN ?

A: DB_FILE_NAME_CONVERT and LOG_FILE_NAME_CONVERT

Q: How to clean FND_NODES table?

A: EXEC FND_CONC_CLONE.SETUP_CLEAN.