hdiutil create -o /tmp/ElCapitan -size 8500m -volname "ElCapitanInstaller" -layout SPUD -fs HFS+J
Please note that the download size is approximately 6.5 GB, and the file name is: Install_Mac_OS_X_El_Capitan_10.11.1.dmg mac-os-x-el-capitan-10-11-1-image-iso
However, for archiving and virtualization, the ISO remains the most versatile. for archiving and virtualization