Which file system to source for adop

One of the big changes for Oracle Applications DBAs in EBS 12.2 is the introduction of online patching.  Instead of using adpatch to apply application patches we now use adop.  In order to allow for online patching Oracle has introduced the dual file system (Run and Patch).  I'm not going to go into a complete explanation of the dual file system in this post, but you can think of it as being two copies of your application file system.  One that is used for your running applications and one that is used to patch against.  When the patching is finished the two file systems switch roles (the patch file system becomes your run file system and vice versa).  The dual file system also brings with it a couple for additional environment variables:

• $FILE_EDITION (e.g. run)
• $RUN_BASE (e.g. /u01/R122_EBS/fs1)
• $PATCH_BASE (e.g. /u01/R122_EBS/fs2)
• $NE_BASE (e.g. /u01/R122_EBS/fs_ne)

You also have a handy environment file "EBSapps.env" located in the Apps Base directory (e.g. /u01/R122_EBS) that you can use to control which environment is being sourced.  You can pass it an argument of "run" or "patch" to tell it which environment you want to use, or otherwise it will prompt you to choose (for more information see MOS Note: 1545584.1) :

. ./EBSapps.env

  E-Business Suite Environment Information

  ----------------------------------------

  RUN File System : /fs1/EBSapps/appl

  PATCH File System : /fs2/EBSapps/appl

  Non-Editioned File System : /fs_ne

  DB Host:  Service/SID:

  E-Business Suite Environment Setting

  ------------------------------------

  - Enter [R/r] for sourcing Run File System Environment file, or

  - Enter [P/p] for sourcing Patch File System Environment file, or

  - Enter anything else to exit

  Would you like to set the E-Business Suite environment [R/P]:R

  Sourcing the RUN File System ...

One common question around the adop utility is which file system should we be sourcing at the various phases of patching (e.g. patch or run).  As it turns out Oracle has made this decision simple for us.  According to the Release 12.2 Oracle E-Business Suite Maintenance Guide it doesn't really matter "The adop utility sets its own environment.  There is therefore no need to source the environment before running it."