Rman Restore SPFILE from controlfile autoback

Once I have wrongly deleted the spfile in our environment.. Thank god the db was up and running so there was no need for the spfile at the time.. Then I have restore the spfile from the controlfile autoback.

If you have configured control file autobackups, the SPFILE is backed up with the control file whenever an autobackup is taken.

If you want to restore the SPFILE from the autobackup, you must first set the DBID for your database, and then use the RESTORE SPFILE FROM AUTOBACKUP command. The procedure is similar to restoring the control file from autobackup. You must first set the DBID for your database, and then use the RESTORE CONTROLFILE FROM AUTOBACKUP command:

RMAN uses the autobackup format and DBID to hunt for control file autobackups, and if a control file autobackup is found, restores the SPFILE from that backup to its default location.

RMAN> SET DBID 1066917090;

RMAN>run {
2> allocate channel c1 type ‘sbt_tape’ parms ‘ENV=(TDPO_OPTFILE=/usr/tivoli/tsm/client/oracle/bin64/emsp_tdpo.opt)’;
3> RESTORE SPFILE to ‘/u01/app/oracle/product/spfiletestdb.ora’ FROM AUTOBACKUP;  ## if you not specifying any location it will                       ##restore to the default location ($ORACLE_HOME)
4> release channel c1;
5> }

allocated channel: c1
channel c1: sid=65 devtype=SBT_TAPE
channel c1: Data Protection for Oracle: version 5.5.1.0

Starting restore at 25-JAN-201212:46:31

channel c1: looking for autobackup on day: 20120125
channel c1: autobackup found: c-849745015-20120125-01
channel c1: SPFILE restore from autobackup complete
Finished restore at 25-JAN-201212:50:01

released channel: c1

RMAN> exit

Unix for DBA

Below are some of the basic unix commands which will be useful for Oracle DBA.

How to kill all similar processes with single command (in this case opmn)

ps -ef | grep opmn |grep -v grep | awk ‘{print $2}’ |xargs -i kill -9 {}

Locating Files under a particular directory

find . -print |grep -i test.sql

Using AWK in UNIX

To remove a specific column of output from a UNIX command – for example to determine the UNIX process Ids for all Oracle processes on server (second column)

ps -ef |grep -i oracle |awk ‘{ print $2 }’

Changing the standard prompt for Oracle Users

Edit the .profile for the oracle user

PS1=”`hostname`*$ORACLE_SID:$PWD>”

Display top 10 CPU consumers using the ps command

/usr/ucb/ps auxgw | head -11

Show number of active Oracle dedicated connection users for a particular ORACLE_SID

ps -ef | grep $ORACLE_SID|grep -v grep|grep -v ora_|wc -l

Display the number of CPU’s in Solaris

psrinfo -v | grep “Status of processor”|wc -l

Display the number of CPU’s in AIX

lsdev -C | grep Process|wc -l

Display RAM Memory size on Solaris

prtconf |grep -i mem

Display RAM memory size on AIX

First determine name of memory device

lsdev -C |grep mem

then assuming the name of the memory device is ‘mem0’

lsattr -El mem0

Swap space allocation and usage

Solaris : swap -s or swap -l

Aix : lsps -a

Total number of semaphores held by all instances on server

ipcs -as | awk ‘{sum += $9} END {print sum}’

View allocated RAM memory segments

ipcs -pmb

Manually deallocate shared memeory segments

ipcrm -m ‘<ID>’

Show mount points for a disk in AIX

lspv -l hdisk13

Display amount of occupied space (in KB) for a file or collection of files in a directory or sub-directory

du -ks * | sort -n| tail

Display total file space in a directory

du -ks .

Cleanup any unwanted trace files more than seven days old

find . *.trc -mtime +7 -exec rm {} \;

Locate Oracle files that contain certain strings

find . -print | xargs grep rollback

Locate recently created UNIX files (in the past one day)

find . -mtime -1 -print

Finding large files on the server (more than 100MB in size)

find . -size +102400 -print

Crontab :

To submit a task every Tuesday (day 2) at 2:45PM

45 14 2 * * /opt/oracle/scripts/tr_listener.sh > /dev/null 2>&1

To submit a task to run every 15 minutes on weekdays (days 1-5)

15,30,45 * 1-5 * * /opt/oracle/scripts/tr_listener.sh > /dev/null 2>&1

To submit a task to run every hour at 15 minutes past the hour on weekends (days 6 and 0)

15 * 0,6 * * opt/oracle/scripts/tr_listener.sh > /dev/null 2>&1

How to find NLS_CHARACTERSET and Lanuage

select DECODE(parameter, ‘NLS_CHARACTERSET’, ‘CHARACTER SET’,
‘NLS_LANGUAGE’, ‘LANGUAGE’,
‘NLS_TERRITORY’, ‘TERRITORY’) name,
value from v$nls_parameters
WHERE parameter IN ( ‘NLS_CHARACTERSET’, ‘NLS_LANGUAGE’, ‘NLS_TERRITORY’)
/