Customizing an AutoConfig Environment & Rolling back an AutoConfig session

1. $AD_TOP/bin/adtmplreport.sh contextfile=$CONTEXT_FILE target=Config file
Use above command to find out template for your configuration file.
2. Once you get the template eg : $AD_TOP/admin/template
create a "custom" directory in $AD_TOP/admin/template
copy  the template to custom directory
do your changes
3. Run autoconfig.
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Customizing an AutoConfig template file delivered by Oracle
If you want to customize an existing AutoConfig template file, perform the following steps (in the order listed):
Determine the AutoConfig template file you want to customize
Execute the following command to find out the corresponding AutoConfig template file for the configuration file you want to customize:  
 Application <AD_TOP>/bin/adtmplreport.sh contextfile=<CONTEXT> target=<configurationfile>
 Database <RDBMS ORACLE_HOME>/appsutil/bin/adtmplreport.sh contextfile=<CONTEXT> target=<configurationfile>
For example, if you want to customize

$COMMON_TOP/html/bin/appsweb_$CONTEXT_NAME.cfg, execute:
On UNIX
$AD_TOP/bin/adtmplreport.sh contextfile=$CONTEXT_FILE \
target=$COMMON_TOP/html/bin/appsweb_$CONTEXT_NAME.cfg
The adtmplreport utility returns the name and location of the AutoConfig template file. For the above UNIX example it would return:
$FND_TOP/admin/template/appsweb.cfg.
You cannot customize all AutoConfig template files. The AutoConfig template file cannot be customized if the "LOCK" keyword appears in the template file's entry in the product driver file. AutoConfig ignores custom template files that are marked with "LOCK". For example, the following entry in  AD_TOP/admin/driver/adtmpl.drv would prevent customization of the file adconfig.txt:
ad admin/template adconfig.txt INSTE8 <s_at>/admin adconfig.txt 600 LOCK

Create the custom template directory
Create a directory named "custom" at the location where the AutoConfig template file resides.
For example, if you want to customize <FND_TOP>/admin/template/appsweb.cfg, execute the following command as the applmgr user:

On UNIX
mkdir $FND_TOP/admin/template/custom

Copy the AutoConfig template file
Copy the AutoConfig template file to the custom template file.
Execute the following command as the applmgr user:

On UNIX
cp -i <AutoConfig template file> <custom template file>
For example:
cp -i $FND_TOP/admin/template/appsweb.cfg \
      $FND_TOP/admin/template/custom/appsweb.cfg


****************>Rolling back an AutoConfig session<******************

Each execution of AutoConfig creates a rollback script in case you need to revert to the previous configuration settings. The script and all backup configuration files from each AutoConfig session are stored in:
Tier  Directory 
Application <APPL_TOP>/admin/<CONTEXT_NAME>/out/<MMDDhhmm>
Database <RDBMS ORACLE_HOME>/appsutil/out/<CONTEXT_NAME>/<MMDDhhmm>

where:<MMDDhhmm> = (month, day, hour, minute of AutoConfig run)
To roll back an AutoConfig session:
On UNIX
restore.sh
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Customizing an AutoConfig Environment [ID 270519.1]
Note 461326.1 - 'Unable to Create a Custom Product TOP'
Using AutoConfig to Manage System Configurations with Oracle Applications 11i [ID 165195.1]
Oracle E-Business Suite Release 11i with 9i RAC: Installation and Configuration using AutoConfig [ID 279956.1]
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