Patching Weblogic 12c using Opatch

2 – Take backup of /path/weblogic/wls1213 (tarball – tar -cvf wls1213.tar wls1213 ) with app user

mkdir  /path/wls1213/OPatch/PATCH_TOP

3. Unzip the patch zip file into the PATCH_TOP.

cd /path/wls1213/OPatch/PATCH_TOP

$ unzip p27419391_121300_Generic.zip

4. Set your current directory to the directory where the patch is located.

$ cd /path/wls1213/OPatch/PATCH_TOP/27419391

4. Run OPatch to apply the patch.

$ opatch apply

PS : in case of any conflict below is oracle recommendation as per SR: SR 3-17746372071

This is the known issue. 
12.1.3.0.0: When this conflict occurs on WLS 12.1.3.0.0, OPatch will stop to prompt the user to proceed with the installation instead of automatically rolling back the previous PSU. 

Action to Take: It is safe to continue the install by pressing Y, and install the January 2018 PSU or newer patch. There is no loss of content. 

So please rollback the previous patch and apply the new one. 

5 – check if applied :

opatch lsinventory -jre /opt/app/java/jdk/jdk180/jre