ORA-01017: invalid username/password; logon denied while creating DB using DBCA

Problem: DBCA ORA-01017 due to OS user/group permissions.

Verify:

1. oracle User: Ensure you're running DBCA as the oracle OS user (or grid for Grid Infrastructure).
2. oinstall Group: Check if oracle (and grid) are in the oinstall group.
   • Command: getent group oinstall | egrep -i 'oracle|grid'
   • Fix (if missing, as root): usermod -a -G oinstall oracle (repeat for grid)
   • Action: Log out and back in as oracle (or grid) after changes.
3. Other Groups: Confirm oracle is in dba and other relevant groups (e.g., asmdba for ASM).
   • Command: id -Gn oracle

Summary: Ensure oracle (or grid) OS user is correctly part of oinstall and other necessary Oracle groups.