Oracle Linux - Using the "find" command to manage files Oracle Database Tips by Donald Burleson

The UNIX/Linux "find" command can be used to locate any external Oracle files including database files (dbf), alert log files, and all trace and dump files

The "which" command can also find files, and we can easily find the location of the SQL*Plus executable:

root> which sqlplus
/u01/home/oracle/product/9.1.2/bin/sqlplus

For non-executable files, you can use the UNIX find command to locate a particular file. Please note that in chapter 8 we extend this command to search for all files that contain specific strings:

root> pwd
/

root> find . -print|grep ?i dbmspool.sql
./oracle/product/9.1.2/rdbms/admin/dbmspool.sql

In the example above, we cd to the root directory (/) and issue a UNIX find command to display every file on the Oracle server.  Next, we pipe the output of the find command to grep, which searches for the dbmspool.sql file.

Below is a script that will automatically remove all trace files from the background_dump_destination filesystem in UNIX.

# Cleanup trace files more than 7 days old
root> find $DBA/$ORACLE_SID/bdump/*.trc -mtime +7 -exec rm {} \;
root> find $DBA/$ORACLE_SID/udump/*.trc -mtime +7 -exec rm {} \;
root> find $DBA/$ORACLE_SID/cdump/*.trc -mtime +7 -exec rm {} \;
Note that the first part of this script (before the ?exec) displays all trace files that are more than 7 days old.
root> find $DBA/$ORACLE_SID/bdump/*.trc -mtime +7

/u01/app/oracle/admin/janet1/bdump/janet1_arc0_25005.trc
/u01/app/oracle/admin/janet1/bdump/janet1_arc0_25173.trc
/u01/app/oracle/admin/janet1/bdump/janet1_arc0_9312.trc
/u01/app/oracle/admin/janet1/bdump/janet1_arc0_9425.trc
/u01/app/oracle/admin/janet1/bdump/janet1_arc1_14300.trc
/u01/app/oracle/admin/janet1/bdump/janet1_arc2_14380.trc
/u01/app/oracle/admin/janet1/bdump/janet1_pmon_25159.trc
/u01/app/oracle/admin/janet1/bdump/janet1_snp0_25171.trc
/u01/app/oracle/admin/janet1/bdump/janet1_snp0_8188.trc
 

Find recent Oracle files

This section issues the UNIX/Linux find command to locate any Oracle trace or dump files that were created in the past day:

#******************************************************
# list the full-names of all possible dump files . . . .
#******************************************************
find $DBA/$ORACLE_SID/bdump/*.trc -mtime -1 -print >> /tmp/trace_list.lst
find $DBA/$ORACLE_SID/udump/*.trc -mtime -1 -print >> /tmp/trace_list.lst
find $ORACLE_HOME/rdbms/log/*.trc -mtime -1 -print >> /tmp/trace_list.lst

Because we know that the grep commands accepts file names as an argument, we can use UNIX xargs command to search each file for our Oracle table name in all sql files. In this case, we search the whole Oracle UNIX directory structure and quickly find all scripts that reference the dba_2pc_pending view.

root> find . -print|grep sql|xargs grep -i dba_2pc_pending

./sql/PENDING.sql:from dba_2pc_pending

Locate recently created Oracle Linux files

The following command is useful for finding Linux files that have been recently added to your server.  Part of the job of the Oracle DBA is monitoring the background_dump_dest and the user_dump_dest for trace files, and purging trace files that are no longer required.

The following command lists all files that were created in the past two weeks:

root> find . -mtime -14 -print

.

./janet1_ora_27714.trc

./janet1_ora_27716.trc

./janet1_ora_24985.trc

./janet1_ora_24977.trc

This command can easily be expanded with the xargs or the ?exec command to automatically remove the elderly trace files:

root> find . -mtime -14 -print|xargs -i rm \;

Note: In Windows you can use this equivalent to the UNIX -mtime check, see equivalent of UNIX mtime for Windows

Finding large files on Linux

The following command is very useful in cases where a Linux file system has become full.  As we may know, Oracle will hang whenever Oracle must expand a tablespace and Oracle cannot extend the UNIX filesystem.

When a UNIX file become unexpectedly full, it may be because Oracle has written a huge core or trace file into the UNIX filesystem.

The script below will display all files that are greaten then one megabyte in size.  Note that the size parameter is specified in K-bytes.

root> find . -size +1024 ?print

./prodsid_ora_22951.trc

Of course, you can easily append the xargs of ?exec command to automatically remove the large file:

root> find . -size +1024 ?print|xargs ?i rm \;

This find command will do a "stats" on all files in a directory structure, showing the total size of all files in the directory.  You can also incorporate the "df -k" command"

find ${START_DIR} -mtime -${DAYS} |xargs stat -c "%s"|awk '{sum += $1}END{print sum}'

 

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